Bladder syringe fluid delivery system

ABSTRACT

A bladder syringe for a fluid delivery system includes a cylindrical body, a cap-bladder assembly, a plunger element disposed in the cylindrical body, and a mounting assembly to secure the cap-bladder assembly to the cylindrical body. The cylindrical body has a distal end and a proximal end and defines a throughbore. The cap-bladder assembly is adapted for connection to the distal end of the cylindrical body, and includes a cap body and a bladder. The cap body defines an interior cavity and a distal discharge conduit and is adapted to engage the distal end of the cylindrical body. A disc-shaped bladder is disposed within the interior cavity and typically includes a central membrane portion. The plunger element is disposed in the throughbore of the cylindrical body and is vented to enable evacuation of the space between the plunger element and the cap-bladder assembly in the cylindrical body.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional of U.S. Ser. No. 13/453,335, filed Apr.23, 2012, which is a continuation-in-part of International ApplicationNo. PCT/US2011/57701 having a filing date of Oct. 25, 2011 and whichclaims the benefit of United Stated Provisional Application No.61/406,453, filed Oct. 25, 2010, the disclosure of each of which areincorporated by this reference.

BACKGROUND Field of the Technology

The present disclosure is related to the medical field and, moreparticularly, disposable syringes used in the medical field in which allor part of the syringe may be disposed of after a single use.

Description of Related Art

It is well known that syringes used in the medical field are typicallydisposable and are discarded after one use. These syringes usuallycomprise a barrel and a plunger mounted for reciprocal movement in thebarrel, both parts usually being made of plastic material. Althoughdisposable syringes are typically made by mass production methods suchas injection molding, such disposable syringes are relatively expensivedue to the materials and precision involved in their manufacture.

In order to reduce manufacturing costs, it has been proposed to combinea reusable syringe barrel and plunger with a replaceable containerpositioned either at the discharge end of the syringe barrel or withinthe syringe barrel. The container is typically flexible and acted uponby the action of the plunger to fill and dispense fluid from thecontainer. For example, the container may be introverted or collapsedupon itself by action of the plunger to eject or administer a medicinalfluid contained in the container. An example of a syringe of this typeis disclosed in U.S. Pat. Nos. 4,236,516 and 4,325,369 to Nilson. In thesyringe disclosed in the foregoing patents, the container forms the endwall of the syringe barrel and comprises a substantially rigid firstwall portion at the exterior side of the end wall and a flexible secondwall portion at the interior side of the end wall. The container isintrovertible upon the inside surface of the first wall portion. Anozzle is provided on the first wall portion for attachment of ahypodermic needle. In the Nilson syringe, as described in the foregoingpatents, the container is formed as a spherical bulb havingsubstantially the same diameter as the cylinder space formed by thesyringe barrel. When an empty container is attached to the syringebarrel, the flexible second wall portion is introverted upon the insidesurface of the first wall portion. To fill the container, the piston iswithdrawn and the flexible wall portion is carried along by the pistondue to sub-atmospheric pressure created between the piston and theflexible wall portion, while liquid such as blood or a medicinal fluidis pulled into the container. However, a substantial sub-atmosphericpressure (vacuum) is created by the piston during the latter part of thewithdrawal stroke thereof, which requires considerable force to beapplied to the piston at the end of the withdrawal stroke necessary forfilling the container. Under certain circumstances, the container maynot be completely filled.

U.S. Pat. No. 4,312,344 to Nilson seeks to overcome the foregoingdeficiencies of the earlier Nilson syringes by providing a rigidspherical container that attaches to the end of the syringe barrel andhas a collapsible spherical bulb attached thereto. This improved Nilsonsyringe further includes a plunger guided for axial movement in thesyringe barrel, and a resilient plunger head connected to the plunger.The plunger has a diameter less than the diameter of the container butcan be deformed to engage the spherical bulb when introverted upon theinside surface of the spherical container over substantially the entiresurface thereof. The rigid spherical container attached to the end ofthe syringe barrel and the resilient plunger head on the plunger addresssome of the operational difficulties with the earlier Nilson syringes.

Other container-type syringes are known in the medical field whichincorporate a bulb portion or bladder element such as may be found inU.S. Pat. No. 798,093 to Dean; U.S. Pat. No. 3,527,215 to De Witt; andU.S. Pat. No. 6,450,993 to Lin. The Dean patent discloses a syringehaving a collapsible bulb portion secured to a glass container via aclamp. The bulb portion is in the form of a diaphragm/bladder that issecured to a cap portion. The De Witt patent discloses a bladder heldwithin a cavity in a needle hub by a retaining ring. The Lin patentdiscloses a half-disposable syringe barrel including a reusable barrelsyringe and a disposable cap member.

Moreover, syringes are known in the medical field that incorporate acollapsible container or bag that is breach-loaded into a syringe barreland then acted upon by a syringe plunger inserted into the syringebarrel to expel the contents of the container. U.S. Pat. No. 2,690,179to Fox and U.S. Pat. No. 3,166,070 to Everett disclose suchcontainer/bag-type syringes. The Everett patent discloses a dispensingsyringe that includes a syringe casing, collapsible bag, and a plungerwith a venting check valve in a passage in the plunger. The Fox patentdiscloses a collapsible container housed within a syringe housing andactuated by a plunger. The plunger includes an air passage in which acheck valve is present to vent air from a forward side of the plungerhead. The container is a sealed bag situated within a head portion ofthe housing and carries a needle assembly. Such container/bag syringesare also used in the blood collection area such as disclosed by U.S.Pat. No. 3,785,367 to Fortin et al. The Fortin patent discloses a rubbercup-shaped member that fits inside a rigid housing attached to a syringebarrel. The rigid housing includes a hollow tapered adapter supportingan arterial needle for collecting an arterial blood sample from apatient which enters a container provided within the syringe barrelunder arterial blood pressure. The syringe barrel includes a reciprocalsyringe plunger therein.

BRIEF SUMMARY

As described in detail herein, one embodiment of a bladder syringe for afluid delivery system comprises a cylindrical body, cap-bladderassembly, and a plunger element disposed in the cylindrical body. Thecylindrical body has a distal end and a proximal end and defines athroughbore. The cylindrical body has an exterior mounting collar at thedistal end of the cylindrical body. The cap-bladder assembly is adaptedfor connection to the distal end of the cylindrical body. Thecap-bladder assembly comprises a cap, a bladder, and a retainer ring tosecure the bladder in the cap. The cap body defines an interior cavity,a distal discharge conduit, and a proximal portion to receive the distalend of the cylindrical body. The proximal portion may have an endadapted to engage the mounting collar on the cylindrical body. Thebladder is typically disc-shaped and disposed within the interior cavityand comprises an outer circumferential rib and a central membraneportion. The plunger element is disposed in the throughbore of thecylindrical body.

The central membrane portion of the bladder may have a non-uniformcross-section. In one variation, the central membrane portion may have aconvoluted central well portion, a plurality of annular ribs, and/or aplurality of radial ribs, or any combination of the foregoing.

The plunger element may comprise a distal portion facing the cap-bladderassembly and a proximal portion adapted for connection with a pistonelement of a power fluid injector. The plunger element may furthercomprise a fluid path allowing gas to pass through the plunger element,and the plunger element may have a one-way check valve in the fluid pathto allow gas to pass through the plunger element and exit at theproximal portion of the plunger element. The plunger element may furthercomprise a seal ring about the proximal portion providing asubstantially fluid tight seal between the plunger element andcylindrical body and an optional guide ring about the distal portion. Aninlet to the fluid path may be disposed between the guide ring and theseal ring.

In another embodiment, the bladder syringe for a fluid delivery systemincludes a cylindrical body, cap-bladder assembly, a plunger elementdisposed in the cylindrical body, and a mounting ring to secure thecap-bladder assembly to the cylindrical body. The cylindrical body has adistal end and a proximal end and defines a throughbore. The cap-bladderassembly is adapted for connection to the distal end of the cylindricalbody and includes a cap body, a bladder, and a retainer ring. The capbody defines an interior cavity, a distal discharge conduit, and aproximal portion to receive the distal end of the cylindrical body. Abladder is disposed within the interior cavity and is typicallydisc-shaped and includes an outer circumferential rib and a centralmembrane portion. The retainer ring is used to secure the bladder in theinterior cavity of the cap body. The plunger element is disposed in athroughbore of the cylindrical body, and the mounting ring secures thecap-bladder assembly to the distal end of the cylindrical body.

In another embodiment, the central membrane portion of the bladder mayhave a non-uniform cross-section. In one variation, the central membraneportion may have a convoluted central well portion, a plurality ofannular ribs, and/or a plurality of radial ribs, or any combination ofthe foregoing.

In another embodiment, the plunger element may comprise a distal portionfacing the cap-bladder assembly and a proximal portion adapted forconnection with a piston element of a power fluid injector. The plungerelement may further comprise a fluid path allowing gas to pass throughthe plunger element, and the plunger element may have a one-way checkvalve in the fluid path to allow gas to pass through the plunger elementand exit at the proximal portion of the plunger element. The plungerelement may further comprise a seal ring about the proximal portionproviding a substantially fluid tight seal between the plunger elementand cylindrical body and an optional guide ring about the distalportion. An inlet to the fluid path may be disposed between the guidering and the seal ring.

Further, in another embodiment, the proximal portion of the cap body maycomprise an exterior structure for engaging a corresponding engagingstructure formed interiorly within the mounting ring to secure thecap-bladder assembly to the distal end of the cylindrical body. Theexterior structure on the proximal portion of the cap body and thecorresponding interior engaging structure within the mounting ring maycomprise interengaging threads.

In another embodiment, a cap-bladder assembly is provided for connectionto a cylindrical body. The cap-bladder assembly comprises a cap, abladder, and a retainer ring. The cap includes a cap body defining aninterior cavity, a distal discharge conduit, and a proximal portion toreceive an end of the cylindrical body. The bladder is typicallydisc-shaped and disposed within the interior cavity and comprises anouter circumferential rib and a central membrane portion. The retainerring is used to secure the bladder in the interior cavity of the capbody. The proximal portion is generally cylindrical-shaped and a conicalportion connects the proximal portion to the discharge conduit. Theproximal portion may have an exterior mounting. The central membraneportion of the bladder may have a non-uniform cross-section. In onevariation, the central membrane portion may have a convoluted centralwell portion, a plurality of annular ribs, and/or a plurality of radialribs, or any combination of the foregoing.

In another embodiment, a bladder syringe and a fluid delivery systemincorporating the bladder syringe are provided. The power fluid injectorcomprises an injector housing and a reciprocally operable pistonelement. The bladder syringe comprises a cylindrical body having adistal end and a proximal end and defines a throughbore. A cap-bladderassembly is adapted for connection to the distal end of the cylindricalbody and comprises a cap comprising a cap body defining an interiorcavity and having a distal discharge conduit. The cap body is seated onthe distal end of the cylindrical body. A disc-shaped bladder isdisposed within the interior cavity and comprises a membrane portion. Aplunger element is disposed in the throughbore of the cylindrical bodyand comprises a distal portion facing the cap-bladder assembly and aproximal portion adapted for connection with the piston element of thepower fluid injector.

A retainer ring may be used to secure the bladder in the interior cavityof the cap body. The membrane portion may have extra material in acentral area of the membrane portion. The membrane portion may define aconvoluted central well portion. The membrane portion may besubstantially planar. The membrane portion may comprise a plurality ofannular ribs or rings. The membrane portion may comprise a plurality ofradial ribs. The membrane portion may have extra material in a centralarea of the membrane portion and define a convoluted central wellportion. The membrane portion may comprise a series of concentricangular-shaped convolutes. The membrane portion may have a thinnercenter section and a thicker outer section tapering from the thinnercenter section. The membrane portion may comprise a series of thickerwall sections near the center of the bladder. The thicker wall sectionsmay be stepped. The membrane portion may have a non-uniformcross-section. The membrane portion may define a central well portionconnected to an outer rim by a series of frangible webs. The membraneportion may be comprised of two or more materials. The membrane portionmay have over-molded ribs on the bottom side thereof. The plungerelement may comprise a distal portion facing the cap-bladder assemblyand a proximal portion adapted for connection with a piston element of apower fluid injector. The plunger element may comprise a vent pathallowing gas to pass through the plunger element to vent the space inthe cylindrical body between the cap-bladder assembly and the plungerelement, and the plunger element may have a one-way check valve in thevent path to allow gas to pass through the plunger element. An inlet tothe vent path is desirably located at a circumferential outer surface ofthe plunger element.

The plunger element may comprise a seal ring providing a substantiallyfluid tight seal between the plunger element and the cylindrical body.

The plunger element may comprise one of an optical, ultrasonic, ormechanical sensor to detect the presence of the cap-bladder assembly onthe distal end of the cylindrical body.

The distal portion of the plunger element and the membrane portion ofthe bladder may be shaped to interact to maintain the bladder materialaligned in the cylindrical body during expansion of the bladder. Themembrane portion may define a convoluted central well portion, and thedistal portion of the plunger element may define a distal circularrecess to interact with the convoluted central well portion. Themembrane portion may define a series or plurality of concentric steppedor ridged portions adapted to cooperate with corresponding concentricstepped or ridged portions on the surface of the distal portion of theplunger element. An optical, ultrasonic, or mechanical sensor may beused to detect the presence of the cap-bladder assembly on the distalend of the cylindrical body.

In another embodiment, a bladder syringe is provided for a fluiddelivery system and comprises a cylindrical body having a distal end anda proximal end and defining a throughbore, and a cap-bladder assemblyadapted for connection to the distal end of the cylindrical body. Thecap-bladder assembly comprises a cap comprising a cap body defining aninterior cavity and a distal discharge conduit. The cap body is seatedon the distal end of the cylindrical body. A disc-shaped bladder isdisposed within the interior cavity and comprises a membrane portion. Aplunger element is disposed in the throughbore of the cylindrical body.A connecting assembly is used to secure the cap-bladder assembly to thecylindrical body. The connecting assembly may comprise an inner sleevefixed to the distal end of the cylindrical body and comprises aplurality of flex legs. The connecting assembly may further comprise anouter sleeve coaxially disposed about the inner sleeve and rotationallyengaged with the inner sleeve such that rotation of the outer sleeve inone direction causes the flex legs to engage the cap body and secure thecap-bladder assembly on the distal end of the cylindrical body androtation in an opposite direction releases the engagement. A distal endof the outer sleeve may be internally curved to engage the flex legs.The flex legs may terminate in a curved distal end to engage theinternally curved distal end of the outer sleeve. The outer sleeve maybe in threaded engagement with the inner sleeve. The flex legs mayterminate in a curved distal end that engages a circumferential rim onthe cap body when the flex legs engage the cap body.

In a further embodiment, a fluid delivery system is provided, comprisinga power fluid injector comprising an injector housing and a reciprocallyoperable piston element, and a bladder syringe. The bladder syringecomprises a cylindrical body having a distal end and a proximal end anddefines a throughbore. A cap-bladder assembly is adapted for connectionto the distal end of the cylindrical body. The cap-bladder assemblycomprises a cap body defining an interior cavity and a distal dischargeconduit, and the cap body is seated on the distal end of the cylindricalbody. A disc-shaped bladder is disposed within the interior cavity andcomprises a membrane portion. A plunger element is disposed in thethroughbore of the cylindrical body and comprises a distal portionfacing the cap-bladder assembly and a proximal portion adapted forconnection with the piston element of the power fluid injector. In use,as the membrane portion is expanded during operation of the bladdersyringe a first material portion of the membrane portion seats againstan interior wall of the cylindrical body and a second material region ofthe membrane portion bridges an area between the interior wall and thedistal portion of the plunger. The distal portion of the plunger elementand the membrane portion of the bladder are interactively shaped suchthat stress in the second material region remains below the rupturestress of the bladder.

The membrane portion may have extra material in a central area of themembrane portion. The membrane portion may define a convoluted centralwell portion. The membrane portion may have extra material in a centralarea of the membrane portion in the form of a convoluted central wellportion. The membrane portion may have a non-uniform cross-section.

The plunger element may comprise a distal portion facing the cap-bladderassembly and a proximal portion adapted for connection with a pistonelement of a power fluid injector. The plunger element may comprise aseal ring providing a substantially fluid tight seal between the plungerelement and the cylindrical body. The seal ring may comprise a lip sealcomprising at least one axial lip. Alternatively, the seal ring maycomprise a double lip seal comprising opposing axial lips.

The distal portion of the plunger element and the membrane portion ofthe bladder may be shaped to interact to maintain the bladder materialaligned in the cylindrical body during expansion of the bladder.

The plunger element may comprise a vent path allowing gas to passthrough the plunger element to vent the space in the cylindrical bodybetween the cap-bladder assembly and the plunger element to atmosphere.A check valve may be provided in the vent path.

A connecting assembly comprising an inner sleeve may be fixed to thedistal end of the cylindrical body and comprises a plurality of flexlegs and an outer sleeve coaxially disposed about the inner sleeve androtationally engaged with the inner sleeve. In use, rotation of theouter sleeve in one direction causes the flex legs to engage the capbody and secure the cap-bladder assembly on the distal end of thecylindrical body and rotation in an opposite direction releases theengagement. A distal end of the outer sleeve may be internally curved toengage the flex legs. The flex legs may terminate in a curved distal endto engage the internally curved distal end of the outer sleeve. Theouter sleeve may be in threaded engagement with the inner sleeve. Theflex legs may terminate in a curved distal end that engages acircumferential rim on the cap body when the flex legs engage the capbody.

Another embodiment is directed to a method of molding a cap-bladderassembly in an injection molding machine, comprising the steps offorming a cap body defining an interior cavity and outer an outercircumferential edge, and forming a disc-shaped bladder within theinterior cavity such that an outer circumferential rib of the bladder ismolded to the outer circumferential edge of the cap body.

The outer circumferential rib of the bladder may be molded to wraparound the outer circumferential edge of the cap body. A central openingis formed in the cap body. The central opening may be formed over aconvoluted central well portion formed in the membrane portion of thebladder. The central opening is defined by a discharge conduit and a capelement may be applied to the discharge conduit seal the dischargeconduit. The bladder may be molded to wrap around the outercircumferential edge of the cap body and radial appendages may be formedto connect to an annular collar disposed around the discharge conduit.The central opening may be formed over a convoluted central well portionformed in the membrane portion of the bladder. The central opening maybe defined by a discharge conduit and a cap element can be applied toseal the discharge conduit. The cap element may comprise a luer endconnector.

Further details and advantages will be understood upon reading thefollowing detailed description in conjunction with the accompanyingdrawings, wherein like parts are designated with like reference numeralsthroughout the several views.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a perspective view of a bladder syringe for a fluid deliverysystem according to one embodiment.

FIG. 1B is a cross-sectional view of the bladder syringe shown in FIG.1A.

FIG. 2 is a detail view of Detail 2 in FIG. 1B.

FIG. 3 is an exploded view showing a cylindrical body, a plungerelement, and a mounting ring of the bladder syringe shown in FIGS.1A-1B.

FIG. 4 is an exploded and cross-sectional view of various components inFIG. 3.

FIG. 5 is an exploded view of a cap-bladder assembly of the bladdersyringe shown in FIGS. 1A-1B.

FIG. 6 is an exploded and cross-sectional view of cap-bladder assemblyin FIG. 5.

FIG. 7 is a cross-sectional view showing a fluid delivery systemutilizing the bladder syringe shown in FIGS. 1A-1B.

FIG. 8 is a partial cross-sectional view of the bladder syringe of FIGS.1A-1B showing the interaction between the bladder and the plungerelement of the bladder syringe during forward movement of the plungerelement.

FIG. 9 is a partial cross-sectional view of the bladder syringe of FIGS.1A-1B showing the interaction between the bladder and the plungerelement of the bladder syringe during rearward movement of the plungerelement.

FIG. 10A is a cross-sectional view of the bladder syringe of FIGS. 1A-1Bshowing another embodiment of the plunger element and the interactionbetween the bladder and the plunger element during movement of theplunger element.

FIG. 10B is a detail view of Detail 10B in FIG. 10A.

FIGS. 11A-11E are cross-sectional views of various seal rings orelements for the various embodiments of the plunger element for thebladder syringe of FIGS. 1A-1B.

FIGS. 12A-12B are respective perspective and cross-sectional views of afirst embodiment of the bladder for a cap-bladder assembly for thebladder syringe of FIGS. 1A-1B.

FIGS. 12C-12D are respective perspective and cross-sectional views of amodification of the first bladder embodiment of FIGS. 12A-12B.

FIGS. 13A-13B are respective perspective and cross-sectional views ofthe first embodiment of the bladder shown in FIGS. 12A-12B and furthershowing a retainer ring for holding the bladder in the cap-bladderassembly for the bladder syringe of FIGS. 1A-1B.

FIGS. 14A-14B are respective perspective and cross-sectional views of asecond embodiment of the bladder for a cap-bladder assembly for thebladder syringe of FIGS. 1A-1B.

FIGS. 15A-15B are respective perspective and cross-sectional views of athird embodiment of the bladder for a cap-bladder assembly for thebladder syringe of FIGS. 1A-1B.

FIGS. 16A-16B are respective perspective and cross-sectional views of afourth embodiment of the bladder for a cap-bladder assembly for thebladder syringe of FIGS. 1A-1B.

FIGS. 17A-17B are respective perspective and cross-sectional views of afifth embodiment of the bladder for a cap-bladder assembly for thebladder syringe of FIGS. 1A-1B.

FIGS. 18A-18B are respective perspective and cross-sectional views of asixth embodiment of the bladder for a cap-bladder assembly for thebladder syringe of FIGS. 1A-1B.

FIGS. 19A-19B are respective perspective and cross-sectional views of aseventh embodiment of the bladder for a cap-bladder assembly for thebladder syringe of FIGS. 1A-1B.

FIGS. 20A-20B are respective perspective and cross-sectional views of aneighth embodiment of the bladder for a cap-bladder assembly for thebladder syringe of FIGS. 1A-1B.

FIGS. 21A-21B are respective perspective and cross-sectional views of aninth embodiment of the bladder for a cap-bladder assembly for thebladder syringe of FIGS. 1A-1B.

FIGS. 22A-22B are respective perspective and cross-sectional views of atenth embodiment of the bladder for a cap-bladder assembly for thebladder syringe of FIGS. 1A-1B.

FIGS. 23A-23B are respective perspective and cross-sectional views of aneleventh embodiment of the bladder for a cap-bladder assembly for thebladder syringe of FIGS. 1A-1B.

FIGS. 24A-24B are respective perspective and cross-sectional views of atwelfth embodiment of the bladder for a cap-bladder assembly for thebladder syringe of FIGS. 1A-1B.

FIGS. 25A-25B are respective perspective and cross-sectional views of athirteenth embodiment of the bladder for a cap-bladder assembly for thebladder syringe of FIGS. 1A-1B.

FIGS. 26A-26B are respective perspective and cross-sectional views of afourteenth embodiment of the bladder for a cap-bladder assembly for thebladder syringe of FIGS. 1A-1B.

FIGS. 27A-27B are respective perspective and cross-sectional views of afifteenth embodiment of the bladder for a cap-bladder assembly for thebladder syringe of FIGS. 1A-1B.

FIGS. 28A-28B are respective perspective and cross-sectional views of asixteenth embodiment of the bladder for a cap-bladder assembly for thebladder syringe of FIGS. 1A-1B.

FIGS. 29A-29B are respective perspective and cross-sectional views of aseventeenth embodiment of the bladder for a cap-bladder assembly for thebladder syringe of FIGS. 1A-1B.

FIGS. 30A-30B are respective perspective and cross-sectional views of aneighteenth embodiment of the bladder for a cap-bladder assembly for thebladder syringe of FIGS. 1A-1B.

FIGS. 31A-31B are respective perspective and cross-sectional views of anineteenth embodiment of the bladder for a cap-bladder assembly for thebladder syringe of FIGS. 1A-1B.

FIGS. 32A-32B are respective perspective and cross-sectional views of atwentieth embodiment of the bladder for a cap-bladder assembly for thebladder syringe of FIGS. 1A-1B.

FIGS. 33A-33B are respective perspective and cross-sectional views of atwenty-first embodiment of the bladder for a cap-bladder assembly forthe bladder syringe of FIGS. 1A-1B.

FIGS. 34A-34B are respective perspective and cross-sectional views of atwenty-second embodiment of the bladder and the cap-bladder assembly forthe bladder syringe of FIGS. 1A-1B.

FIGS. 35A-35B are respective perspective and cross-sectional views of abladder and plunger element having cooperating surface texturing for usein the bladder syringe of FIGS. 1A-1B.

FIG. 36 is a perspective view showing the cylindrical body of thebladder syringe with interior surface texturing to reduce slidingfriction between the bladder and the interior wall of the cylindricalbody.

FIG. 37 is a schematic cross-sectional view of the bladder syringe ofFIGS. 1A-1B in which the bladder for the cap-bladder assembly is in theform of a rolling diaphragm.

FIG. 38 is a schematic cross-sectional view of the bladder syringe ofFIGS. 1A-1B in which the bladder for the cap-bladder assembly is in theform of a bellows.

FIGS. 39A-39B are a perspective view of a bladder and a schematiccross-sectional view, respectively, of the bladder syringe of FIGS.1A-1B in which the bladder for the cap-bladder assembly is in the formof a cup-shaped distal portion having a depending rolled-up portion.

FIG. 40 is a schematic cross-sectional view of the bladder syringe ofFIGS. 1A-1B in which the bladder is mechanically operated by the plungerelement.

FIG. 41 is a schematic cross-sectional view of the bladder syringe ofFIGS. 1A-1B in which the bladder has a tapered profile to match theinterior of a cap of the cap-bladder assembly.

FIGS. 42A-42B are respective perspective and schematic cross-sectionalviews of another embodiment of the bladder syringe in which the bladderis in the form of a flexible body that fits within the inner diameter ofthe cylindrical body of the bladder syringe, and the cap of thecap-bladder assembly is a solid planar end cap.

FIGS. 43A-43C are schematic cross-sectional views of another embodimentof the bladder syringe that incorporates a dual vacuum plunger element.

FIGS. 44A-44B are respectively a schematic cross-sectional view and across-sectional view of another embodiment of the bladder syringe and abladder therefor, each set at an angle to allow for more surface area ofcontact between the bladder and the plunger element.

FIGS. 45A-45B are respective schematic cross-sectional views of anotherembodiment of the bladder syringe in which the cap-bladder assembly isbreach-loaded into the cylindrical body of the bladder syringe.

FIGS. 46A-46C are respective schematic cross-sectional views of anotherembodiment of the bladder syringe in which a dual diaphragm arrangementin the cap-bladder assembly is driven by a fluid displacement actuator.

FIGS. 47A-47F are respective schematic views showing variations informing the cap-bladder assembly according to co-injection moldingand/or over-molding techniques.

FIG. 48 is a schematic cross-sectional view of another embodiment of thebladder syringe that incorporates a sensor in the plunger element.

FIG. 49 is a schematic cross-sectional view of another embodiment of thebladder syringe that incorporates a sensor and a vacuum tube in theplunger element.

FIG. 50 is a schematic cross-sectional view of another embodiment of thebladder syringe that incorporates a pressure sensor in the plungerelement.

FIG. 51 is a schematic cross-sectional view of another embodiment of thebladder syringe that incorporates a vacuum-activated sensor in theplunger element.

FIG. 52 is a partial cross-sectional view of the bladder syringe ofFIGS. 1A-1B having a contact impedance measurement system for detectingpresence of the cap-bladder assembly and/or leaking of a bladder in thecap-bladder assembly.

FIG. 53 is a schematic cross-sectional view of another embodiment of thebladder syringe having a sensing arrangement to mechanically sense thepresence of the cap-bladder assembly on the cylindrical body of thebladder syringe.

FIG. 54 is a partial cross-sectional view showing the bladder syringe ofFIGS. 1A-1B with an additional light pipe assembly for detecting thepresence of a cap-bladder assembly on the cylindrical body of thebladder syringe.

FIG. 55 is a schematic cross-sectional view of the bladder syringe ofFIG. 54 with an alternative embodiment of the light pipe assembly.

FIG. 56 is a schematic cross-sectional view of another embodiment of thebladder syringe having an optical sensor array provided to read groovesin the cap body of the cap-bladder assembly on the cylindrical body ofthe bladder syringe.

FIGS. 57-58 are respective schematic cross-sectional views of anotherembodiment of the bladder syringe in which an external sensor device isused to detect the presence and position of the bladder and/or todetermine the volume of fluid present in the bladder, or otherproperties associated with the bladder.

FIGS. 59A-59B are respective schematic cross-sectional views of anotherembodiment of the bladder syringe in which the bladder is provided withfloating fibers.

FIGS. 60A-60B are respective schematic cross-sectional views of anotherembodiment of the bladder syringe in which a floating actuator isprovided inside the cap-bladder assembly and which only allows fluidinjection if fluid is present in the bladder.

FIG. 61 is a schematic cross-sectional view of the bladder syringe ofFIGS. 1A-1B showing the bladder syringe with a fluid transfer set andfurther having a flow regulation and monitoring capability.

FIGS. 62A-62B are respective schematic cross-sectional views of anotherembodiment of the bladder syringe in which the interior wall of thecylindrical body of the bladder syringe and/or the interior of the capin the cap-bladder assembly has surface texturing that becomes visuallyclear when exposed to liquid.

FIGS. 63A-63B are respective schematic cross-sectional views of anotherembodiment of the bladder syringe in which a sensor array is provided inthe interior wall of the cylindrical body of the bladder syringe.

FIG. 64 is a cross-sectional view of the bladder syringe of FIGS. 1A-1Bhaving two (2) sensor elements in the cap of the cap-bladder assembly.

FIGS. 65A-65C are a perspective and two cross-sectional views,respectively, of another embodiment of the bladder syringe in which thecap-bladder assembly has an optical detection assembly that detectslight reflectance changes in the presence of fluid in the cap of thecap-bladder assembly.

FIG. 66 is a schematic cross-sectional view of another embodiment of thebladder syringe in which the plunger element has a hollow cavity orwell.

FIG. 67 is a schematic cross-sectional view of another embodiment of thebladder syringe in which a flapper or duckbill valve is incorporatedinto the cap of the cap-bladder assembly.

FIG. 68 is a schematic cross-sectional view of another embodiment of thebladder syringe in which the bladder may comprise a second safety liner.

FIGS. 69A-69B are respective schematic cross-sectional views of anotherembodiment of the bladder syringe in which the bladder covers a rear orproximal end of the cylindrical body of the bladder syringe.

FIGS. 70A-70B are respective schematic cross-sectional views of two (2)embodiments of the cap-bladder assembly having different high-crackpressure bi-directional check valves disposed to control fluid into andfrom a discharge conduit in the cap of the cap-bladder assembly.

FIGS. 71A-71C are, respectively, a perspective view, a schematiccross-sectional view, and a detail view of detail 71C in FIG. 71B ofanother embodiment of the bladder syringe that incorporates analternative arrangement for securing the cap-bladder assembly to thecylindrical body.

FIGS. 72A-72B are two perspective views of a fluid injector foroperating the bladder syringe and show another arrangement for securingthe cap-bladder assembly to the cylindrical body of the bladder syringe.

FIG. 73A is an exploded view of another embodiment of the bladdersyringe incorporating another arrangement for securing the cap-bladderassembly to the cylindrical body of the bladder syringe.

FIGS. 73B-73C are exploded views showing progressive states of assemblyfor the bladder syringe of FIG. 73A.

FIGS. 73D-73E are cross-sectional views of the embodiment of the bladdersyringe of FIGS. 73A-73C showing, respectively, unlocked and lockedstates for the cap-bladder assembly on the cylindrical body of thebladder syringe.

FIG. 74A is an exploded perspective view of an adapter assembly forconnecting the plunger element of the bladder syringe to a conventionalor known plunger.

FIG. 74B is a schematic cross-sectional view of an embodiment of thebladder syringe incorporating the adapter assembly of FIG. 74A.

FIG. 75 is a cross-sectional view of the cap-bladder assemblyprepackaged with two removable shipping caps.

FIG. 76 is a cross-sectional view of a cup-shaped packaging containerfor the cap-bladder assembly of the bladder syringe.

FIG. 77 is a perspective view of a packaging container with a multi-wellbody for the cap-bladder assembly of the bladder syringe.

FIG. 78 is a perspective view of a packaging container with asingle-well body for receiving several cap-bladder assemblies in anend-to-end relationship, wherein the discharge conduits on therespective cap-bladder assemblies.

FIG. 79 is a perspective view of a packaging container with asingle-well body for receiving several cap-bladder assemblies in anend-to-end relationship, wherein the open ends of the caps of thecap-bladder assemblies face one another.

FIG. 80 is a perspective view of a plurality of cap-bladder assembliespackaged on a long bandolier protective strip.

FIGS. 81A-81B are a perspective view and a cross-sectional view,respectively, of a packaging container in which the cap of thecap-bladder assembly forms an integral part of the packaging container.

FIG. 82 is an exploded perspective view of the bladder syringe in whichthe cap-bladder assembly is secured to the cylindrical body by a bayonetmounting connection.

FIG. 83 is a top view of the cylindrical body shown in FIG. 82.

FIG. 84 is a perspective view of a fluid injector wherein thearrangement for securing the cap-bladder assembly to the cylindricalbody shown in FIGS. 73A-74E is provided on the front of the fluidinjector.

FIG. 85 is a side view of the cap-bladder assembly according to anotherembodiment.

FIGS. 86-87 are cross-sectional views showing the steps of engaging thecap-bladder assembly shown in FIG. 85 with a cylindrical body adapted toaccept the cap-bladder assembly.

FIG. 88 is an exploded perspective view showing another embodiment forsecuring the cap-bladder assembly to the cylindrical body for thebladder syringe.

FIG. 89 is a top view of a clam shell mounting cap adapted to enclosethe cap-bladder assembly, and further includes an isolation view of thecap-bladder assembly according to the embodiment shown in FIGS. 73A-73E.

FIG. 90 is a perspective view showing use of the clam shell mounting capof FIG. 89 for mounting the cap-bladder assembly to the cylindricalbody.

FIG. 91 is a side view of a split mounting ring that may be used todirectly secure the cap-bladder assembly to the cylindrical body.

FIG. 92 is a perspective view showing a front-loading pressure jacketstructure with a front retaining plate that may be used to secure thecap-bladder assembly in association with a cylindrical pressure jacket.

FIG. 93 is a cross-sectional view showing another embodiment forsecuring the cap-bladder assembly to the cylindrical body for thebladder syringe, wherein the cylindrical body comprises a threadedmounting collar adapted to engage exterior threads provided on the outersurface or circumference of the cap body of the cap of the cap-bladderassembly.

FIG. 94 is a perspective view showing another embodiment for securingthe cap-bladder assembly using an over-center clamp assembly.

FIG. 95 is a cross-sectional view showing the cap-bladder assembly in adual or ganged form.

FIG. 96 is a perspective view showing the dual cap-bladder assembly ofFIG. 95.

FIG. 97 is a perspective view of a fluid injector adapted to accept thedual cap-bladder assembly of FIGS. 95-96.

FIG. 98 is a cross-sectional view of bladder syringe according toanother embodiment comprising an inflatable or expandable fluid sealbetween the cap-bladder assembly and the cylindrical body.

FIG. 99 is a schematic cross-sectional view and a top view,respectively, of a rotatable protector cap that is rotatably disposed ona cap body of the cap of the cap-bladder assembly.

FIG. 100 is a cross-sectional view of the bladder syringe according toanother embodiment having a plurality of bladders.

FIG. 101 is a cross-sectional view of the bladder syringe of FIG. 100 inan operational state.

FIG. 102 is a perspective view of another embodiment of the cap-bladderassembly with a large central opening in the discharge conduit on thecap body of the cap.

FIG. 103 is a transverse cross-sectional view of a cap-bladder assemblyof FIG. 103.

FIG. 104 is a perspective view of a modification of the embodiment ofthe cap-bladder assembly shown in FIGS. 102-103.

FIG. 105 is a transverse cross-sectional view of a cap-bladder assemblyof FIG. 104.

FIG. 106 is a cross-sectional view of the bladder syringe showing aplunger element in the cylindrical body, and showing the plunger elementwith another embodiment of the seal ring or element.

FIG. 107 is a cross-sectional and isolation view of the seal ring usedwith the plunger element shown in FIG. 106.

FIG. 108 is a cross-sectional view of the bladder syringe showing aplunger element in the cylindrical body, and showing the plunger elementwith another embodiment of the seal ring or element.

FIG. 109A is a cross-sectional and isolation view of the seal ring usedwith the plunger element shown in FIG. 108.

FIG. 109B is a cross-sectional and isolation view of a modification tothe seal ring shown in FIG. 109A.

FIGS. 110A-110C are respective cross-sectional views showing three (3)different bladder shapes and plunger element shapes that each havedifferent performance characteristics.

FIG. 111 is a schematic cross-sectional view of a generalized bladdersyringe used to describe the phenomena associated with the movement,playing out, drawing out, or deployment of the bladder during operation.

DETAILED DESCRIPTION

For purposes of the description hereinafter, spatial orientation terms,as used, shall relate to the referenced embodiment as it is oriented inthe accompanying drawing figures or otherwise described in the followingdetailed description. However, it is to be understood that theembodiments described hereinafter may assume many alternative variationsand configurations. It is also to be understood that the specificcomponents, devices, and features illustrated in the accompanyingdrawing figures and described herein are simply exemplary and should notbe considered as limiting.

Referring initially to FIGS. 1-7 and particularly FIG. 7, a fluiddelivery system 10 generally comprises a power fluid injector head 12,such as a Stellant® power injector platform manufactured by Medrad,Inc., and a bladder syringe 20 as described in detail herein. As isknown in the medical field, injecting contrast media into thebloodstream of patients enables visualization of various pathologiesthrough X-Ray, Computed Tomography (CT), Magnetic Resonance (MR), orother medical imaging modalities. Contrast delivery is most effectiveand efficient using a power injector, such as the Stellant® powerinjector, that can be programmed to deliver specific amounts of contrastagent and/or saline at specific flow rates. A power injector may be usedin diagnosing stroke, heart disease, cancer, vascular disease, physicalinjury, digestive disorder, etc. The fluid injector 12 comprises two (2)linearly reciprocal piston elements 14 which each have a distal pistoninterface 16 adapted to engage a syringe plunger disposed within asyringe body. The piston elements 14 are enclosed within a housing 18and specific details of a power injector platform and syringe elementsused therewith may be found in U.S. Pat. No. 5,383,858 to Reilly et al.;U.S. Pat. No. 5,873,861 to Hitchins et al.; and U.S. Pat. No. 6,652,489to Trocki et al., all assigned to Medrad, Inc. and each incorporatedherein by reference for disclosure related to the foregoing elements.This disclosure is explicitly not limited to utilizing the bladdersyringe 20 with contrast media but may be used for any medicinal fluidto be delivered to a patient.

The bladder syringe 20 is a multi-component or composite devicegenerally comprising a mounting ring 22, a cylindrical body 30, aplunger element 50 disposed in the cylindrical body 30, and acap-bladder assembly 100 comprising a cap 102, retainer ring 140, and abladder 1140. The bladder syringe 20 is adapted for use in CT, MR andlike procedures and operable at typical operating pressures of about300-400 psi, and the bladder 1140 may be expanded to hold fluid volumeson the order of 200 ml. The cap-bladder assembly 100 is adapted to besecured to the cylindrical body 30 by the mounting ring 22. Each of theforegoing components is discussed hereinafter in detail. The cylindricalbody 30 is a unitary, typically, cylindrical body having a distal end 32and a proximal end 34 and is typically a reusable component, while thecap-bladder assembly 100 is typically a single-use component. Thecylindrical body 30 has an interior wall 36 that defines a throughbore37 between the distal and proximal ends 32, 34. The proximal end 34 isadapted to interface with the fluid injector 12 and includes acircumferential flange 38 positioned to engage the front end of thehousing 18 of the fluid injector 12 to properly seat the cylindricalbody 30 relative to the fluid injector 12. Additionally, in theillustrated embodiment, two opposed bayonet attachment flanges 40 areprovided at the proximal end 34 for interfacing with the fluid injector12 to secure the cylindrical body 30 to the fluid injector 12. Furtherdetails relating to the circumferential flange 38 and attachment flanges40 used to properly interface the cylindrical body 30 with the fluidinjector 12 may be found in the foregoing Medrad, Inc. patents whichdiscuss similar interfacing features for securing a Stellant® CT syringeto a Stellant® fluid injector. While the foregoing interfacing features38, 40 provided on the cylindrical body 30 are described for interfacingthe cylindrical body 30 to a Stellant® fluid injector, this descriptionis provided for exemplary purposes and the proximal end 34 of thecylindrical body 30 may have any suitable configuration for interfacingwith any suitable power fluid injector known in the medical field forpower fluid delivery applications. The Stellant® fluid injector and theproximal end features of a Stellant® syringe, as described in theforegoing Medrad, Inc. patents, are provided for exemplary purposes onlyand should not be considered limiting. For example, the interfacebetween the proximal end 34 of the cylindrical body 30 and fluidinjector 12 may take other front-loading arrangements as disclosed inthe foregoing Trocki et al. patent, or in U.S. Pat. No. 7,419,478 toReilly et al. and assigned to Medrad, Inc. (additionally incorporatedherein by reference). An adapter may also be used to connect thecylindrical body 30 to the fluid injector 12 as disclosed in U.S. Pat.No. 5,520,653 to Reilly et al., or in U.S. Pat. No. 7,497,843 toCastillo et al. and U.S. Pat. No. 6,726,657 to Dedig et al., allassigned to Medrad, Inc. and incorporated herein by reference for theseteachings. All of the foregoing Medrad, Inc. patents disclose variousapparatus and methods for mounting a syringe body to a fluid injector,whether a single-syringe fluid injector or multi-syringe fluid injector,and, further, disclose various apparatus and methods for interfacing asyringe plunger with a piston element of the fluid injector. Thus, thesepatents are incorporated by reference into this disclosure at least forteaching apparatuses and methods for interfacing the cylindrical body 30to the fluid injector 12 and, further, for interfacing the pistonelement or elements 14 of the fluid injector 12 with a plunger element50 disposed within the cylindrical body 30. Suitable embodiments of asyringe plunger may also be found in the foregoing Medrad, Inc. patentswhich may be utilized for the plunger element 50, augmented with theinternal passageways and flow path elements described herein inconnection with the plunger element 50 that are specific for use withthe cap-bladder assembly 100. Further, the housing 18 of the fluidinjector 12 may comprise a light ring (not shown) that can encompass allor part of the axial length of the cylindrical body 30 and all or partof the cap-bladder assembly 100 to sterilize the cylindrical body 30 andall or part of the cap-bladder assembly 100 with ultraviolet light (UV).Additionally, cylindrical body 30 may comprise a barrier or membrane(not shown) within the bore 37 near the proximal end 34 of thecylindrical body 30 that acts as a barrier to keep fluid from enteringthe injector housing 18 in the event of failure of the bladder 1140. Thebarrier forms a reservoir chamber that catches spilled fluid.

The distal end 32 of the cylindrical body 30 is formed with an exteriormounting collar 42. Additionally, the distal end 32 of the cylindricalbody 30 is formed with an end flange or collar 44 having a tapered rim45 for interfacing with the cap-bladder assembly 100. The mountingcollar 42 is axially spaced from the end flange 44 and a recess orgroove 46 is defined between the mounting collar 42 and the end flangeor collar 44. This recess or groove 46 is provided with a sealing O-ring48 for forming a substantially fluid-tight or leak proof seal with thecap-bladder assembly 100 as described hereinafter. The cylindrical body30 may be made of any suitable plastic material, desirably a clearplastic material, such as, but not limited to, polycarbonate, acrylic,or polyester.

In brief, during the operation of the bladder syringe 20, as the pistonelement 14 of the fluid injector 12, which is connected to the plungerelement 50 in the cylindrical body 30, retracts in the throughbore 37 ofthe cylindrical body 30, a vacuum is generated in the space between theplunger element 50 and the bladder 1140 of the cap-bladder assembly 100which expands the bladder 1140 to draw in fluid. To generate andmaintain a vacuum in the cylindrical body 30, the sealing O-ring 48 isused to maintain a generally fluid-tight seal between the cap-bladderassembly 100 and the cylindrical body 30, and an additional seal ring 88(discussed in detail herein) is provided about the plunger element 50 toestablish and maintain a generally fluid-tight seal between the plungerelement 50 and the interior wall 36 of the cylindrical body 30. Aspliced hollow O-ring may be used in place of the sealing O-ring 48 tolower the insertion force of the cap-bladder assembly 100 over theO-ring 48. A lubrication coating may also be added to the sealing O-ring48.

The mounting ring 22 is used to secure the cap-bladder assembly 100 tothe cylindrical body 30 as described in detail herein. The mounting ring22, in the embodiment illustrated, is of split-ring construction formedby two half-ring portions 24. Each half-ring portion 24 has an L-shapedwall in transverse cross-section which is defined by a longer axial wall25 and a shorter, inward-extending radial wall 26. When the respectivehalf-ring portions 24 are joined together to form the mounting ring 22,the radial walls 26 define an inner diameter of the mounting ring 22that is approximately equal to or slightly larger than the outerdiameter of the cylindrical body 30. In this manner, the radial walls 26of each half-ring portion 24 may engage the mounting collar 42 on thecylindrical body 30 in interference engagement in an axial direction ofthe cylindrical body 30. Additionally, the mounting collar 42 desirablyextends radially outward sufficiently to seat against the interior sideof the axial wall 25 of each half-ring portion 24. The axial wall 25 ofeach of the half-ring portions 24 further includes one or moreinward-extending radial tabs or threads 28 to engage with correspondingstructures, such as tabs or threads, on the cap-bladder assembly 100 asdescribed herein. While not shown in detail in the accompanying figures,inter-engaging structures may be provided to join together the terminalends of the respective half-ring portions 24 to form the mounting ring22. Such inter-engaging structures may be of a nature to provide areleasable snap-fit connection between the terminal ends of therespective half-ring portions 24. Other suitable releasable connectionsbetween the terminal ends of the respective half-ring portions 24 may beused, such as by use of a mechanical connection using mechanicalfasteners, adhesives, ultrasonic welding, or interference fits. Ifdesired, the two half-ring portions 24 may be joined together at oneterminal end with a hinge structure, such as a living hinge, so thatonly one securing arrangement is needed to secure the remaining freeterminal ends of the two half-ring portions 24 together to assemble themounting ring 22 and secure the same in association with the cylindricalbody 30 and the cap-bladder assembly 100. This hinged configuration isakin to a clamshell arrangement.

The plunger element 50 is disposed within the cylindrical body 30 andcomprises, in the embodiment shown in FIGS. 1B and 4, a two-piece bodyformed by a distal or top portion 52 and a proximal or rear portion 54.The proximal portion 54 includes a pair of legs 56 for interfacing withthe piston interface 16 on the piston elements 14 of the fluid injector12. If desired, this interface may be a fusible link in that should thisinterface become wet with liquid, such as may occur when the bladder1140 leaks or ruptures, the link breaks preventing further reciprocalmovement of the plunger element 50 (e.g., the plunger element 50mechanically disconnects from the piston element 14). The legs 56 on theproximal portion 54 of the plunger element 50 are adapted so that thepiston interface 16 may engage the plunger element 50 to capture theplunger element 50 whereby the piston element 14 may reciprocally movethe plunger element 50 within the cylindrical body 30. As an example,the legs 56 may flex apart when contacted by the piston interface 16 sothat the interface 16 enters the space between the flex legs 56. Theflexibility of the flex legs 56 is such that the flex legs 56 may snaponto a flange or like structure on the piston interface 16 whereby thecapture of the plunger element 50 by the piston interface 16 of thepiston element 14 may be completed. A suitable embodiment of the flexlegs 56 may be found in the foregoing Reilly et al. (U.S. Pat. No.5,383,858) or Hitchins et al. patents, which were incorporated herein byreference. The distal portion 52 of the plunger element 50 may comprisea central post 58 that engages a corresponding pocket 60 defined by theproximal portion 54, and the engagement of the distal portion 52 to theproximal portion 54 may be accomplished by a frictional engagementbetween the central post 58 and the pocket 60. A suitable medical gradeadhesive may further be provided at the interface between the centralpost 58 and the pocket 60 to secure the connection between the distalportion 52 and the proximal portion 54. A mechanical fastener may alsobe used in addition or apart from the foregoing adhesive connectionbetween the distal portion 52 and the proximal portion 54, or thesecomponents may be ultrasonically welded together as another alternative.

The distal portion 52 of the plunger element 50 may be formed with anannular chamber 62 about the central post 58 and a pair ofaxially-directed passageways 64 is located radially outward on eitherside of the annular chamber 62. The respective axial passageways 64 arein fluid communication with the bore 37 of the cylindrical body 30 viaan intersecting radial passageway 66 that extends outward to acircumferential outer surface 68 of the distal portion 52 of the plungerelement 50. A porous plug or filter similar to the porous plug 134described herein in connection with FIGS. 10A-10B may be provided in theradial passageway 66 to prevent bladder 1140 from “extruding” into theradial passageway 66 during operation. The annular chamber 62 may alsobe formed as two separate passageways on either side of the central post58 if desired. The proximal portion 54 of the plunger element 50 islikewise formed with a pair of axially-directed passageways 70 thatgenerally correspond to/align with the axial passageways 64 in thedistal portion 52 of the plunger element 50. The respective axialpassageways 70 in the proximal portion 54 of the plunger element 50generally have a larger diameter than the corresponding axialpassageways 64 in the distal portion 52 of the plunger element 50 and,further, each define an optional reduced diameter portion 72 extendingto a proximal or rear surface 74 of the proximal portion 54 of theplunger element 50. Moreover, the proximal portion 54 of the plungerelement 50 comprises a distal-facing rim 76 formed radially outward fromthe respective axial passageways 70 and which is shaped and positionedto engage a corresponding receiving annular groove or recess 78 definedin a proximal-facing side of the distal portion 52 of the plungerelement 50. The engagement between the distal-facing rim 76 on theproximal portion 54 of the plunger element 50 and the proximal annulargroove 78 in the distal portion 52 of the plunger element 50 may be africtional engagement augmented with a suitable medical grade adhesiveif desired. Additionally, an internal O-ring 80 may be disposed at theinterface between the distal-facing rim 76 on the proximal portion 54 ofthe plunger element 50 and the proximal annular groove 78 in the distalportion 52 of the plunger element 50, if desired, to provide a fluidtight seal between the distal portion 52 and the proximal portion 54. Asnoted previously, a mechanical fastener may also be used in addition orapart from an adhesive connection between the distal portion 52 and theproximal portion 54, or these components may be ultrasonically weldedtogether as another alternative which eliminates the need for themechanical fastener, an additional securing adhesive, and, further, theinternal O-ring 80.

Further, a one-way check valve 82 may be seated or disposed in each ofthe axial passageways 70 in the proximal portion 54 of the plungerelement 50. The check valves 82 may be duckbill-type check valves havinga preset opening pressure. Other suitable valve designs may also be usedand the check valves 82 are not limited to duckbill-type check valves.Moreover, while the check valves 82 are presented in this disclosure inconnection with the plunger element 50, a single valve 83, as shown inFIG. 1A, may alternatively be provided in the sidewall of thecylindrical body 30 just below the cap-bladder assembly 100 and theaxial location of the bladder 1140 in the bore 37 of the cylindricalbody 30 to vent air from the cylindrical body 30. In this alternativeconfiguration, as the plunger element 50 moves forward in thecylindrical body 30 toward the cap-bladder assembly 100, air is forcedout of the cylindrical body 30 via the sidewall check valve 82, and asthe plunger element 50 retracts rearward or proximally in thecylindrical body 30, the sidewall check valve 82 closes to establish avacuum in the cylindrical body 30. The inlets to the respective axialpassageways 70 in the proximal portion 54 of the plunger element 50 maybe shaped to seat or support the respective check valves 82. Thus, thecheck valves 82 provide the interface between the axial passageways 64in the distal portion 52 of the plunger element 50 and the axialpassageways 70 in the proximal portion 54 of the plunger element 50. Thecircumferential or radial outer surface 68 of the distal portion 52 ofthe plunger element 50 is shaped to define a tapered annular space Awith the interior wall 36 of the cylindrical body 30. Additionally, theradial outer surface 68 of the distal portion 52 of the plunger element50 supports a guide ring 84 disposed in a circumferential groove orrecess provided in the radial outer surface 68. Similarly, acircumferential or radial outer surface 86 of the proximal portion 54 ofthe plunger element 50 defines a circumferential groove or recess forsupporting a sealing O-ring 48 or “seal ring” 88 that provides agenerally fluid-tight or leak proof seal with the interior wall 36 ofthe cylindrical body 30.

Referring additionally to FIGS. 8-9, also discussed further herein, afluid, namely air, vent path 90 is established through the plungerelement 50 due to the foregoing internal configuration of the plungerelement 50 to allow venting of the airspace in the bore 37 distal orforward of the plunger element 50 when the cap-bladder assembly 100 isdisposed on the distal end 32 of the cylindrical body 30. This vent path90 is generally defined as having an inlet at an inlet port 92 to theradial passageway 66 in the distal portion 52 of the plunger element 50which is located at the radial outer surface 68 of the distal portion 52of the plunger element 50 and desirably in close proximity to the sealring 88. The vent path 90 extends through the radial passageway 66 tothe axial passageway 64 in the distal portion 52 of the plunger element50 and, further, through the check valve 82 and the axial passageway 70in the proximal portion 54 of the plunger element 50. The vent path 90has an outlet or exit at an outlet or exit port 94 at the reduceddiameter portion 72 of the axial passageway 70 in the proximal portion54 of the plunger element 50. The outlet or exit port 94 of the axialpassageway 70 in the proximal portion 54 of the plunger element 50 isshown located at the proximal or rear surface 74 of the proximal portion54 of the plunger element 50 but may be at any location proximal orrearward of the seal ring 88.

The annular space A about the radial outer surface 68 of the distalportion 52 of the plunger element 50 is defined generally between theradial outer surface 68 and the interior wall 36 of the cylindrical body30 to allow airflow to reach the inlet port 92 to the radial passageway66 in the distal portion 52 of the plunger element 50. The annular spaceA is provided for limiting the potential for the bladder 1140 to bepinched against the interior wall 36 of the cylindrical body 30 byoperation of the plunger element 50. Additionally, the guide ring 84disposed about the radial outer surface 68 of the distal portion 52 ofthe plunger element 50 is shaped and sized to permit airflow to reachthe inlet port 92 to the radial passageway 66 in the distal portion 52of the plunger element 50.

In particular, the guide ring 84 is located distal of the inlet port 92to the vent path 90 and is designed to have minimal clearance with theinterior wall 36 of the cylindrical body 30 to allow air to reach theinlet port 92. However, this clearance is small enough to keep thematerial of the bladder 1140 in the cap-bladder assembly 100 from beingpulled over or into the inlet port 92 to the vent path 90, therebyobstructing air flow into the vent path 90 through the plunger element50. In other words, the guide ring 84 generally keeps the material ofthe bladder 1140 from being “pinched” between the radial outer surface68 of the distal portion 52 of the plunger element 50 and the interiorwall 36 of the cylindrical body 30 which could obstruct air flow intothe inlet port 92 to the vent path 90 through the plunger element 50.The guide ring 84 may alternatively be designed to contact the interiorwall 36 of the cylindrical body 30, but may include a slot or slots (notshown) in the outer circumference of the guide ring 84 to allow air topass to the inlet port 92 of the vent path 90. The inlet port 92 of thevent path 90, which is the inlet to the radial passageway 66 in thedistal portion 52 of the plunger element 50, could also incorporate aflap or a porous plastic cover, as discussed herein in connection withFIG. 10B, to protect the inlet port 92 during operation of the plungerelement 50 to fill or dispense fluid from the bladder 1140. Inparticular, such a flap or porous plastic cover is used to protect thebladder 1140 from “extruding” into the inlet port 92 and may eliminatethe need for a separate guide ring 84. As a result, the seal ring 88 maybe used to prevent the bladder 1140 from being “pinched” between thedistal portion 52 of the plunger element 50 and the interior wall 36 ofthe cylindrical body 30.

As shown in FIGS. 1B and 4, the inlet port 92 is located axially betweenthe guide ring 84 disposed about the radial outer surface 68 of thedistal portion 52 of the plunger element 50 and the seal ring 88 isdisposed about the radial outer surface 86 of the proximal portion 54 ofthe plunger element 50. FIGS. 8-9 alternatively illustrate that, ifdesired, the guide ring 84 may be formed integrally with the distalportion 52 of the plunger element 50 rather than being a separate ringstructure disposed about the distal portion 52. A further comparisonbetween FIGS. 1B, 4 and 8-9 shows that a mounting mechanical fastener 96may additionally be used to secure the connection between the centralpost 58 on the distal portion 52 and the corresponding pocket 60 definedby the proximal portion 54 of the plunger element 50.

Moreover, from FIGS. 1B, 4, and 8-9, it will be clear that two distinctvent paths 90 are present through the plunger element 50 due to theinternal passage configuration of the plunger element 50. Such dual ventpaths 90 are ideally provided on opposing lateral sides of the plungerelement 50 as will be clear from FIGS. 1B and 4. However, FIGS. 8-9alternatively show that only one such vent path 90 may be needed inaccordance with this disclosure to allow venting of the airspace in thebore 37 of the cylindrical body 30, distal or forward of the plungerelement 50 when the cap-bladder assembly 100 is disposed on the distalend 32 of the cylindrical body 30. Additionally, FIGS. 8-9 alternativelyshow that the locations for the distal-facing rim 76 and the annulargroove or recess 78 may be reversed, with the rim 76 being formed on theproximal-facing side of the distal portion 52 of the plunger element 50and the annular groove or recess 78 being formed in the distal-facingside of the proximal portion 54 of the plunger element 50. Furthermore,FIGS. 8-9 illustrate that the distal portion 52 of the plunger element50 may optionally define a rounded point or nub 98 for interfacing with(for supporting, holding, and centering) the bladder 1140 of thecap-bladder assembly 100 such as a central well portion 1148 of thebladder 1140 shown in FIGS. 12-13 discussed herein. The respectiveO-rings comprising the internal ring 80, guide ring 84, and seal ring 88may be made of any suitable sealing elastomeric material such assilicone, EPDM, nitrile, and urethane and may have a lubrication coatingapplied thereto. Suitable materials for forming the distal and proximalportions 52, 54 of the plunger element 50 include plastic materials suchas, but not limited to, ABS or polycarbonate.

As will be understood from comparing FIG. 1B and FIGS. 8-9, the distalportion 52 of the plunger element 50 may comprise different shapes, withthe embodiment shown in FIGS. 8-9 comprising a distal point or nub 98.Differing shapes for the distal portion 52 can lead to differentefficiencies for purging air from the cylindrical body 30 in theairspace forward of the plunger element 50. The distal portion 52 mayexhibit the shape shown in FIG. 1B or FIGS. 8-9 and, further, mayexhibit an elongated conical shape with a rounded tip or end much likeFIG. 1B or an elongated conical shape with a distal point or nub 98.Such an extended or elongated conical shape may have different taperangles such as 10°, 30°, or 45° from horizontal, as examples. In theembodiment shown in FIGS. 8-9, the distal portion 52 with the extendedpoint or nub 98 provides more surface area to resist the distribution ofthe bladder 1140 toward the interior wall 36 of the cylindrical body 30during withdrawal operation of the plunger element 50 in the bladdersyringe 20. Additionally, surface texturing, as shown in FIGS. 35A-35Bdiscussed herein, such as external ribs on the distal portion 52 of theplunger element 50 may increase the resistance to the distribution ofthe bladder 1140 to the interior wall 36 of the cylindrical body 30during withdrawal operation of the plunger element 50 in the bladdersyringe 20. Corresponding surface features such as texturing may also beprovided on the membrane portion 1146 of the bladder 1140 facing theplunger element 50 as well (FIGS. 35A-35B).

The cap-bladder assembly 100 is generally adapted for connection withthe distal end 32 of the cylindrical body 30 and this connection issecured with the mounting ring 22, as mentioned previously. Thecap-bladder assembly 100 is typically intended to be a single-usecomponent which may be adapted for use with the cylindrical body 30,while the cylindrical body 30 may be reused multiple times for fluiddelivery applications and potentially for multiple patients. Thecylindrical body 30, or base, serves as a pressure jacket for thebladder 1140 in the cap-bladder assembly 100. Thus, the cap-bladderassembly 100 is the portion of the bladder syringe 20 that is used tocontain contrast media and/or flushing media or other medicinal fluidthat is injected into a patient for diagnostic or treatment purposes.The piston elements 14 of the fluid injector 12 provide the forcesneeded to move the plunger element 50 within the bore 37 of thecylindrical body 30, and the vent path 90 through the plunger element 50enables the airspace within the bore 37 between the plunger element 50and the bladder 1140 to be vented to the atmosphere as a result of themovement of the plunger element 50. In particular, forward or distalmovement of the plunger element 50 in the bore 37 of the cylindricalbody 30 in the direction of arrow A₁ in FIG. 8 permits the airspacedistal of the plunger element 50 and enclosed by the cap-bladderassembly 100 to be vented to the atmosphere via the vent path 90described previously, and reverse or proximal movement of the plungerelement 50 in the direction of arrow A₂ in FIG. 9 creates a vacuum inthis space. This vacuum pressure acts upon the cap-bladder assembly 100to fill the bladder 1140 of this assembly 100 with a desired injectionfluid. Once filled with a desired amount of injection fluid, subsequentforward or distal operation of the piston element 14 of the fluidinjector 12 in the direction of arrow A₁ in FIG. 8 causes the injectionfluid to be dispensed from the cap-bladder assembly 100. While thediscussion in this disclosure provides for drawing a vacuum in the bore37 of the cylindrical body 30 to operate the bladder therein, it mayalso be possible to fill the bladder 1140 with pressurized fluid via thedischarge conduit 110 on the cap body 104 of the cap 102 and use aregulator (not shown) in the discharge conduit 110 to limit outputpressure of the fluid.

The cap-bladder assembly 100 generally comprises a cap 102 adapted forconnection to the distal end 32 of the cylindrical body 30, adisc-shaped bladder 1140 which is disposed within the interior of thecap 102, and a retainer ring 140 used to secure the disc-shaped bladder1140 within the cap 102. The cap 102 comprises a unitary cap body 104defining an interior cavity 106. The cap body 104 includes a tapered orconical portion 108 that terminates in a distal discharge luer-typeconduit 110 optionally having a threaded end connector 112. The distaltapered or conical portion 108 is connected radially to a cylindricalportion in the form of an annular skirt or sidewall that is sized toreceive the distal end 32 of the cylindrical body 30 therein. In certainembodiments of the cap 102, the cylindrical distal portion 114 of thecap body 104 may be omitted, as in FIG. 47C described herein as oneexample. The conical portion 108 provides structural rigidity for thecap-bladder assembly 100. Desirably, an electrical contact 115 a may beprovided on the end flange 44 at the distal end 32 of the cylindricalbody 30 that is adapted to engage an opposing electrical contact 115 bon the interior side of the cylindrical portion 114 of the cap body ofthe cap 102, and an electrical connection may be established between theopposing electrical contact 115 a, 115 b when the cap-bladder assembly100 is mounted to the distal end 32 of the cylindrical body 30. Thispresence sensing arrangement may be communicated to the controller forthe fluid injector 12 so that the presence of the cap-bladder assembly100 on the cylindrical body 30 can be confirmed. The cylindrical portion114 comprises a sidewall 116. The interior cavity 106 is generallydefined by the distal conical portion 108 and the cylindrical portion114 of the cap body 104. The opposing electrical contacts 115 a, 115 bmay be provided between the cap body 104 and the distal end 32 of thecylindrical body 30 in the embodiment shown in FIG. 1A.

The cap body 104 optionally includes a cylindrical distal portion 118 inthe form of an annular skirt that extends forward or distally from theradial wall connecting the distal conical portion 108 to the cylindricalportion 114 to partially enclose or shield the distal conical portion108 and can further serve as a drip catcher. The cylindrical distalportion 118 is shown omitted from FIG. 1A. The cylindrical distalportion 118 is of a height that permits the distal discharge conduit 110to extend outward from the distal conical portion 108. The exterior ofthe cap body 104 may have one or more finger flanges 120 bridging thecylindrical portion 114 and the cylindrical distal portion 118 to allowfor easy handling of the cap 102 and the assembly of the cap 102 withthe cylindrical body 30 and the mounting ring 22. However, thecylindrical distal portion 118 may be omitted, as shown in FIG. 1A,wherein the finger flanges are provided on the cap body 104 to bridgethe conical portion 108 and the cylindrical portion 114. Additionally,the cylindrical portion 114 of the cap body 104 includes exterior tabsor threads 122 to engage with the inward-extending radial tabs orthreads 28 on the half-ring portions 24 forming the mounting ring 22 tosecure the cap 102 to the distal end 32 of the cylindrical body 30. Thedistal conical portion 108 of the cap body 104 includes a dependinginterior annular rib or rim 124 to interface with the bladder 1140 andwith the retainer ring 140 used to maintain the bladder 1140 within theinterior cavity 106 of the cap body 104. The annular rib or rim 124defines a circumferential recess or groove 126 with the cylindricalportion 114 which accepts a portion of the bladder 1140 therein. Theengagement of the bladder 1140 with this recess or groove 126 is securedby the retainer ring 140. Additionally, the cylindrical portion 114includes one or more axially-extending tabs 128 to engage or interfacewith the retainer ring 140 to aid in securing the retainer ring 140 andthe accompanying bladder 1140 within the interior cavity 106 of the capbody 104. Further, the axially-extending tabs 128 interface with theretainer ring 140 to prevent rotation thereof in the interior cavity ofthe cap body 104. The cylindrical portion 114 defines a proximal rim orend 130 of the cap body 104 which is adapted to engage or seat againstthe mounting collar 42 on the cylindrical body 30. Additionally, thesidewall 116 of the cylindrical portion 114 defines an internal ledge132 in the interior cavity 106 of the cap body 104 which provides ashoulder for engagement with the radial flange 142 of the retainer ring140.

As described in the foregoing, the disc-shaped bladder 1140 is intendedto be disposed within the interior cavity 106 of the cap body 104. Inthe embodiment shown in FIGS. 1-6, the bladder 1140 is a unitary elementformed with an outer circumferential rib 1142 having a radially-inwardextending portion 1144 and a thinner central membrane portion 1146. Theouter circumferential rib 1142 extends outward from both sides of themembrane portion 1146 and forms the portion of the bladder 1140 that isused to mount the bladder 1140 to the retainer ring 140. In theembodiment illustrated in FIGS. 1-9, the central membrane portion 1146includes a generally W-shaped central well portion 1148, as shown inFIG. 6. The bladder 1140 generally has a top or distal side 1150 whichfaces the distal conical portion 108 of the cap body 104 and a bottom orproximal side 1152 which faces the plunger element 50 when thecap-bladder assembly 100 is connected to the distal end 32 of thecylindrical body 30. One or both sides 1150, 1152 may be coated with alubricious coating to limit frictional interaction with the interiorwall 36 of the cylindrical body 30. The outer rib 1142 is adapted toengage or be received in the groove or recess 126 between the annularrib or rim 124 extending proximally from the distal conical portion 108of the cap body 104 and the sidewall 116 of the cylindrical portion 114of the cap body 104, with the distal-facing side of the radial portion1144 of the outer rib 1142 seated against the annular rib or rim 124.The outer rib 1142 and radial portion 1144 also mount the bladder 1140to the retainer ring 140 as described herein.

The retainer ring 140 generally has an L-shaped transverse cross-sectionformed by a radial flange 142 and an axial flange 144. The retainer ring140 further defines a tapered inner rim 146 that is shaped to engage thetapered rim 45 on the end flange 44 at the distal end 32 of thecylindrical body 30 when the cap-bladder assembly 100 is mounted to thedistal end 32 of the cylindrical body 30. The axial flange 144 has anouter diameter generally corresponding to the inner diameter of theouter rib 1142 of the bladder 1140 so that the axial flange 144 may seatagainst the proximal-facing side of the radial portion 1144 of the outerrib 1142 of the bladder 1140, while the radial flange 142 seats inengagement with the proximal side or end of the outer rib 1142. Theradial flange 142 of the retainer ring 140 further has an outer diametergenerally corresponding to the inner diameter of the sidewall 116 sothat the radial flange 142 may seat against the interior of the sidewall116 of the cap body 104. The frictional engagement between the outerdiameter of the radial flange 142 and the inner diameter of the sidewall116 of the cylindrical portion 114 of the cap body 104 is generallysufficient to maintain the retainer ring 140 and the bladder 1140supported by the retainer ring 140 in place within the interior cavity106 of the cap body 104 prior to and during assembly of the cap-bladderassembly 100 on the distal end 32 of the cylindrical body 30. Inparticular, the illustrated radial flange 142 is segmented and includesa series of elongated tabs 148 that define the outer diameter of theradial flange 142 which frictionally engages the interior of thesidewall 116 to maintain the retainer ring 140 and the bladder 1140supported by the retainer ring 140 in place within the interior cavity106 of the cap body 104 prior to and during assembly of the cap-bladderassembly 100 on the distal end 32 of the cylindrical body 30. Betweenthe tabs 148, a series of recesses 150 is provided to interengage withthe one or more axially-extending tabs 128 on the cylindrical portion114 of the cap body 104 to prevent rotation of the retainer ring 140 inthe interior cavity 106. The foregoing interengaging feature between theretainer ring 140 and the cap body 104 serves to at least partiallyisolate the bladder 1140 from torque applied to the cap 102 when thecap-bladder assembly 100 is secured to the cylindrical body 30. Theengagement of axially-extending tabs 128 with the recesses 150 alsohelps to frictionally hold the retainer ring 140 in place within the cap102. Additionally, it may be desirable to stake-over the edges, forexample by ultrasonic or via cold or hot-staking processes, of theaxially extending tabs 128 once the retainer ring 140 is installed inthe cap 102 to retain the retainer ring 140 therein. The retainer ring140 may be formed of rigid or semi-rigid material, such aspolypropylene, which is also naturally lubricious which reduces frictionbetween the retainer ring 140 and the cap body 104 during assembly.

The foregoing seal arrangement between the bladder 1140 and cap 102 isexternal and radially outward from the operating bore 37 of thecylindrical body 30 wherein the plunger element 50 is operable. As such,a nearly seamless joint is present between the taper rim 45 of thecylindrical body 30 and the inner diameter of the retainer ring 140which the plunger element 50 can ride over with little resistance as theouter rib 1142 sandwiched between the cap body 104 and the cylindricalbody 30 to help form the seamless joint.

In addition to the foregoing configuration of the retainer ring 140which is simply press-fit into the cap 102, the retainer ring 140 may beconfigured to be threaded into the interior cavity 106 of the cap body104. Alternatively, the retainer ring 140 may be designed to “float”once assembled into the cap body 104 for tolerance control.Additionally, the bladder 1140 may also be over-molded to retainer ring140 and assembled to the cap body 104 as described above, or the bladder1140 could be over-molded directly to the cap body 104 and the retainerring 140 would no longer be necessary. Several molding techniques forforming the cap body 104, retainer ring 140, and bladder 1140 aredescribed further herein. The interior cavity 106 of the cap body 104can include undercut tabs (not shown) to help retain the retainer ring140 therein.

Referring next to FIGS. 10A-10B and 11A-11D, another and presentlypreferred embodiment of the plunger element 50 is shown disposed in thebore 37 of the cylindrical body 30. The plunger element 50 shares mostof the features of the embodiments of the plunger element 50 describedpreviously, and generally comprises one vent path 90 through the plungerelement 50 in a similar manner to that shown in FIGS. 8-9. Only relevantdifferences over the previous embodiments of the plunger element 50 willnow be described herein. In the presently preferred embodiment of theplunger element 50, the plunger element 50 comprises a distal portion 52and a proximal portion 54, with the seal ring 88 disposed in a recessdefined at the interface between the distal portion 52 and the proximalportion 54. The radial passageway 66 in the distal portion 52 supports aporous plug 134 that is typically made of porous plastic like Porex®. Asdepicted, the radial passageway 66 is provided in the distal portion 52of the plunger element 50 on the same side as the bladder 1140.Typically, the radial passageway 66 is provided so that the inlet port92 of the vent path 90 and, hence, to the porous plug 134, is locatednear the outer edge of the distal portion 52 of the plunger element 50.In the depicted embodiment, this entrance location is on the taperingportion of the distal portion 52 of the plunger element 50. Thisembodiment may optionally include a protective flap or cover 136, asshown in FIG. 10B, to prevent the bladder 1140 from extruding into theinlet port 92. The protective flap or cover 136 opens and closesdepending fluid pressure within the cylindrical body 30. The location ofthe porous plug 134 is important for proper air purge during filling ofthe bladder 1140 because the bladder 1140 eventually seals the inletport 92 of the porous plug 134 during fluid filling preventing air frompassing through the vent path 90. Thus, it is desirable to locate theinlet port 92 leading to the porous plug 134 near the outer edge orcircumference of the distal portion 52 of the plunger element 50 on thesame side as the bladder 1140 for proper venting of the airspace abovethe plunger element 50. The present embodiment of the plunger element 50also has a distal portion 52 comprising a distal circular recess 138that surrounds a flat nub or ledge 139. This particular configurationhas been found to work well with the bladder 1140 shown, for example, inFIG. 6 having a membrane portion 1146 with a W-shaped convoluted centralwell portion 1148 because the interaction between the distal circularrecess 138 and ledge 139 and the extra material present in the W-shapedconvoluted central well portion 1148 maintains the bladder materialaligned in the cylindrical body 30 during expansion/elongation of thebladder 1140 and thereby enables greater stretching or filling of thebladder 1140. In any of the embodiments of the plunger element 50 andcylindrical body 30, it is desirable to form the cylindrical body 30 ofa material with a low coefficient of friction to allow for easierrelease of bladder 1140 and reduce the possibility of having the bladder1140 pinch under the seal ring 88. Furthermore, while a passive porousplug 134 with optional flap or cover 136 is described in the foregoing,this arrangement may be replaced by a controlled vent such as anelectromechanical device that is actively controlled by a controllerassociated with the fluid injector 12 to open and close the vent path 90as desired and at appropriate times to fill and dispense fluid from thebladder syringe 20. The two halves 52, 54 of the plunger element 50 maybe designed and assembled to compress the seal ring 88 and limitpotential pinching of the bladder 1140. For example, features may beprovided to either half 52, 54 to control the amount and location ofseal compression.

Additionally, FIGS. 11A-11D illustrate various different embodiments ofthe seal ring 88 that may be used with the plunger element 50 in any ofthe embodiments of this disclosure. As is well-known, dynamic sealsincrease the force applied to a syringe wall as pressure increases. FIG.11A shows a suitable quad seal as the seal ring 88 and FIG. 11D shows adynamic U-cup seal as the seal ring 88. Dynamic type seals may help keepthe bladder 1140 from extruding past the seal ring 88 at higher pressureand speeds of the piston element 14 of the fluid injector 12. As theseal ring 88 is used to seal the vacuum in the cylindrical body 30, thedynamic seal ring 88 as shown in FIG. 11D is designed to increase thesealing pressure against the interior wall 36 of the cylindrical body30. FIG. 11C illustrates another embodiment of a seal ring 88 in theform of an O-ring energized cap seal and FIG. 11B illustrates a sealring 88 as described previously. The seal ring 88 and guide ring 84 maybe made of internally lubricated seal materials, Teflon® and the like,or low friction coatings may be provided on these seals or on theinterior wall 36 of the cylindrical body 30 to reduce friction andincrease the life of the seals. Proper lubrication of the seals 84, 88is desirable to prevent the bladder 1140 from “extruding” past the seal.Additionally, silicone may be applied to the distal portion 52 of theplunger 550 and/or provided on the proximal side 1152 of the membraneportion 1146 of each bladder 1140 during manufacturing to maintainlubrication on the interior wall 36 of the cylindrical body 30 formaintenance of the seals 84, 88 as well as lower the friction betweenthe bladder 1140 and the interior wall 36. Further, the seals 84, 88 maybe anti-extrusion seals made from hydrophobic material wherein air canpass through the vent air from behind bladder 1140, but if fluidcontacts these seals the pathway becomes obstructed preventing fluidfrom reaching the interior of the plunger element 50 and the checkvalves 82 therein. Furthermore, one or both of the seals 84, 88 may bemoisture sensitive so that in case of a leak or rupture of the bladder1140 during use, one or both seals 84, 88 expand and inhibit or preventmovement of the plunger element 50. As an alternative to the sealarrangements shown in FIGS. 11A-11D, as shown in FIG. 11E, cylindricalseal 89 may be seated in the bore 37 of the cylindrical body 30 thatslides or rolls as the plunger element 50 moves within the bore 37. Thecap-bladder assembly 100, cylindrical body 30, and the plunger element50 are shown schematically in FIG. 11E for simplicity and details ofthese components and their interaction may be found in the foregoing.

Moreover, it is also desirable to coat the proximal side 1152 of thebladder 1140 with a lubricant that may be transferred to the interiorwall 36 of the cylindrical body 30 during filling. This coating mayalternatively be an antibiotic/antibacterial coating that may also belubricant based and with each expansion of the bladder 1140 to theinterior wall 36 of the cylindrical body 30, the lubricant coating,antibiotic or antibacterial coating, or lubricant-based antibioticcoating is transferred to the interior wall 36 and this coating isfurther transferred to the plunger element 50, which likewise may beindependently coated with an antibiotic or antibacterial coating, orlubricant-based antibiotic coating. Furthermore, the distal and proximalportions 52, 54 of the plunger element 50, cylindrical body 30, and/orbladder 1140 may be molded from antibiotic materials for sterilityenhancement.

In general, it is desirable to provide the cap-bladder assembly 100 inprepackaged form, such as sealed in a sterile state within a packagingcontainer. Such a prepackaged form can maintain the sterility of thecap-bladder assembly 100 until the packaging is opened and thecap-bladder assembly 100 is removed therefrom. Several differentpackaging embodiments for the cap-bladder assembly 100 are describedlater in this disclosure. However, it is generally desirable that thecap-bladder assembly 100 arrive for use at a medical facility with thebladder 1140 secured in place by the retainer ring 140 within theinterior cavity 106 of the cap body 104 in the manner described in thepreceding paragraphs. As a result, the medical practitioner at themedical facility only needs to open the packaging, remove thecap-bladder assembly 100 therefrom, and mate the cap-bladder assembly100 with cylindrical body 30 as described herein.

In a typical fluid injection procedure involving the fluid deliverysystem 10, the fluid injector 12 is usually prepositioned within amedical imaging suite of a hospital or other medical facility and may bepermanently affixed somewhere within the imaging suite. The medicalpractitioner may perform several preparatory steps to prepare the fluidinjector 12 for a fluid injection procedure, such as setting up andprogramming the controller of the fluid injector 12 for the specifiedfluid injection procedure. At least one of these preparatory stepsideally includes mounting the proximal end 34 of the cylindrical body 30to the fluid injector 12 by whatever mounting procedure is required tomate the cylindrical body 30 to the fluid injector 12. If the fluidinjector 12 is a two-syringe injector, two cylindrical bodies 30 will beconnected to the fluid injector 12. As noted previously, the cylindricalbody 30 may be reusable at least to a limited degree by number of fluidinjections and/or patients. The cylindrical body 30 with plunger element50 and mounting ring 22 may be prepackaged in their own container andone of the preparatory steps will include opening the prepackagedcontainer and removing one or more cylindrical bodies 30 therefrom. Ifdesired, the piston elements 14 of the fluid injector 12 may be moved toa fully extended position.

Thereafter, the cap-bladder assembly 100 may be secured to the distalend 32 of the cylindrical body 30. This is generally accomplished byfirst placing the split mounting ring 22 in engagement with mountingcollar 42 on the distal end 32 of the cylindrical body 30. Then, thecap-bladder assembly 100 may be removed from its packaging and thecylindrical portion 114 of the cap body 104 may be placed over the endflange 44 on the distal end 32 of the cylindrical body 30. The taperedrim 45 on the end flange 44 facilitates the placement of the cylindricalportion 114 over the distal end 32 of the cylindrical body 30. Once theone or more exterior radial tabs or threads 122 on the cylindricalportion 114 of the cap body 104 begin to interface with thecorresponding interior tabs or threads 28 in the mounting ring 22, thecap body 104 may then be rotated or otherwise manipulated to completethe engagement between the mating sets of tabs or threads 28, 122. Anend feature, such as a tab or rib, on the exterior threads 122 on thecap body 104 contacts a corresponding feature, such as a tab or rib, onthe engaging threads 28 within the mounting ring 22 to prevent furtherrotation of the cap 102 relative to the mounting ring 22. At this point,the rim or end 130 on the cap body 104 may be in an axial position wherethe proximal rim or end 130 seats against the mounting collar 42 on thecylindrical body 30. Additionally, the tapered inner rim 146 in theretainer ring 140 seats in engagement with tapered rim 45 on the endflange 44 at the distal end 32 of the cylindrical body 30. A generallyfluid-tight or leak proof seal is provided by the O-ring 48 disposedbetween the cylindrical portion 114 of the cap body 104 and the distalend 32 of the cylindrical body 30, with the threaded engagement providedby mating threads 28, 122 compressing the O-ring 48 between thecylindrical portion 114 of the cap body 104 and the distal end 32 of thecylindrical body 30 for a fluid-tight engagement. The engagement of thetapered inner rim 146 in the retainer ring 140 with the tapered rim 45on the end flange 44 at the distal end 32 of the cylindrical body 30traps the outer rib 1142 of the bladder 1140 axially within thecircumferential recess or groove 126 defined between the annular rib orrim 124 and the sidewall 116 of the proximal cylindrical portion 114 ofthe cap body 104. The exterior finger flanges 120 allow for easyhandling of the cap body 104 during the assembly of the cap 102 with thecylindrical body 30. In the present embodiment, alignment between themating sets of tabs or threads 28, 122 is not required before rotationof the cap body 104 begins.

A disposable fluid set 200, as shown in FIG. 1A, may be associated withthe bladder syringe 20 by joining this set 200 to the threaded endconnector 112 at the end of the discharge conduit 110 of the cap body104. Alternatively, the disposable fluid set 200 may be provided as anintegral part of the discharge conduit 110 of the cap body 104. Thedisposable fluid set 200 may include one or more tubing elements 201terminating in a container spike or another medical connector element202 for placing the bladder syringe 20 in fluid communication with oneor more bottles or bags containing desired injection fluids. The capbody 104 may comprise a pinch valve or block 203, which is formed aspart of one of the finger flanges 120 in FIG. 1A, for pinching thetubing element 201 and preventing unwanted outflow from the bladdersyringe 20. The pinch valve or block 203 may simply be provided as atube holder.

In the foregoing description, the cap-bladder assembly 100 attaches tothe cylindrical body 30 by a screw thread engagement and this engagementmay feature a multiple start thread to reduce rotation required forassembly of the cap-bladder assembly 100 to the cylindrical body 30.This thread geometry also reduces the rotation required for completeassembly. However, this threaded connection may be equivalently replacedby a bayonet connection similar to that provided by attachment flanges40 on the cylindrical body 30 that mate with the injector housing 18 ofthe fluid injector 12. In the foregoing description, the mounting ring22 is formed from two identical pieces to form a clamshell around thecylindrical body 30. These two half-ring portions 24 may alternativelybe secured together around the cylindrical body 30 with screws, as notedpreviously. The two half-ring portions 24 could also be secured to thecylindrical body 30 using a press fit (as noted previously), ultrasonicwelding, heat staking, or through the use of adhesives. The clamshellconfiguration of the two half-ring portions 24 may also contain featureswhich provide visual, tactile, and audible feedback to the user when thecap-bladder assembly 100 is fully engaged on the cylindrical body 30.

Once the cap-bladder assembly 100 is fully engaged on the cylindricalbody 30, fluid filling and air purging operations involving the bladdersyringe 20 may be conducted. The cylindrical body 30 may be secured tothe faceplate by a removable pin and the like to prevent rotationrelative to the piston element 14 and piston interface tip 16 duringoperation. The fluid filling and air purging operations involve fillingthe bladder 1140 with a desired injection fluid and purging of air frombehind the filled bladder 1140. Once all of the desired fluid suppliesare associated with the disposable fluid set 200 connected to thebladder syringe 20, a filling sequence may be initiated by an operator.The filling sequence fills the bladder 1140 and the supply lines of thedisposable fluid set 200 and this sequence may be done manually orautomatically based on the programming of the fluid injector 12. In theautomatic mode, volume indicators on the fluid injector head 12 willindicate how much fluid needs to be loaded to support the injectionprotocol including the amount of fluid necessary to air-purge and primethe tubing associated with the disposable fluid set 200. When a Fillbutton (not shown) is pressed on the fluid injector 12, the fluidinjector 12 automatically retracts the piston elements 14 to draw in apredetermined amount of injection fluid. The piston elements 14 thenstop and advance to expel any air that was drawn into the bladder 1140.The piston elements 14 then automatically retract again until the volumerequired to perform the injection is loaded into the bladder 1140 plusan additional amount of fluid, such as 10 ml, as an example. The pistonelements 14 then pause for a short period of time, for example 5seconds, to ensure all fluid is drawn into the bladder 1140 then advanceto the final volume. The fluid injection procedure may then be initiatedby the attendant operator by pressing a Start button (not shown) on thefluid injector 12. Ideally, the fluid injector 12 automatically performsan air check for air in the tubing of the disposable fluid set 200and/or the bladder syringe 20 either in preparation for the fluidinjection procedure or during the fluid injection procedure or in bothinstances. Once the fluid injection procedure is completed, thecap-bladder assembly 100 may be removed from the cylindrical body 30 anddiscarded. The cylindrical body 30 may remain in place and be reused ormay be replaced as desired by attendant medical personnel. The foregoingfilling and air purging operations may be done manually in that anattendant operator for the fluid injector 12 may conduct the steps insequence rather than relying on the programming provided in thecontroller associated with the fluid injector 12. The fluid injector 12may have a weight sensor (not shown) in the fluid injector housing 18that can detect an increase in weight of one or both of the bladdersyringes 20 shown in FIG. 7, indicating that fluid is present in one orboth of the bladders 1140 of the bladder syringes 20. The weight sensormay further include a measurement device to determine gross air presentin the bladder syringe(s) 20 versus a fully liquid-filled syringe(s) 20.

Referring to FIGS. 8-9, it is desirable for the plunger element 50 towork in conjunction with the bladder 1140 to maximize fill volume. Whenthe bladder 1140 contacts the interior wall 36 of the cylindrical body30 during filling when the plunger element 50 moves in the direction ofarrow A₂, the vacuum behind the bladder 1140 can restrain the bladder1140 against the interior wall 36 of the cylindrical body 30 forcingfurther expansion of the bladder 1140 to come from material that is notcurrently in contact with the interior wall 36, (e.g., from the centerof the membrane portion 1146). The plunger element 50 may interact withthe bladder 1140 to restrict movement of the bladder 1140 outwardtowards the interior wall 36 of the cylindrical body 30, which conservesthe bladder material (e.g., thickness) in the center of the membraneportion 1146 as the plunger element 50 is retracted in the cylindricalbody 30 in the direction of arrow A₂ and the bladder 1140 expands.Accordingly, those embodiments of the bladder 1140 to be discussedherein that comprise extra material or features on the membrane portion1146 as shown, for example, in FIGS. 12-13 and 15-21, as non-limitingexamples, allow for increased or enhanced fill volumes. Several designfeatures built into the plunger element 50 and/or bladder 1140 canincrease adhesion of the bladder 1140 to the distal portion 52 of theplunger element 50. These design features include, as above, a thickersection in the center of the membrane portion 1146 of the bladder 1140or additional material through addition of convolutes (e.g., additionalcurves/curvature of the membrane portion 1146), a steeper angle of taperfor the distal portion 52 of the plunger element 50, or a plunger tip orpoint 98 with a steep angle to increase surface area in contact with thebladder 1140. An increase in the coefficient of friction between thebladder 1140 and distal portion 52 of the plunger element 50 may alsoincrease fill volumes. This increase in the coefficient of friction maybe accomplished, for example, through material selection and/orinterengaging surface features such as surface texturing on the distalportion 52 of the plunger element 50 and the membrane portion 1146 ofthe bladder 1140 such as interlocking steps, ribs, or grooves on themembrane portion 1146 and the distal portion 52 of the plunger element50, as discussed herein in connection with FIGS. 35A-35B. Further, asnoted previously, the plunger element 50 with a distal portion 52 havinga distal circular recess 138 that surrounds a flat nub or ledge 139 hasbeen found to work particularly effectively with the bladder 1140 shown,for example, in FIG. 6 having a membrane portion 1146 with a W-shapedconvoluted central well portion 1148.

As also noted previously, the vent path 90 through the plunger element50 controls the flow of air and liquid in and out of the bladder syringe20. In FIGS. 8-9, retraction of the plunger element 50 in the bladdersyringe 20 creates a vacuum which expands the bladder 1140 to fill thebladder 1140 with fluid. Advancement of the plunger element 50 dispensesfluid from the filled bladder 1140. Proper filling of the bladdersyringe 20 requires a high vacuum level behind the bladder 1140 in thespace in the cylindrical body 30 between the plunger element 50 and thebladder 1140. To start the fluid fill process, it is desirable thatthere be as little air behind the bladder 1140 as possible in order togenerate a high vacuum. The one-way check valves 82 in the plungerelement 50 facilitate removal of air behind the bladder 1140. As shownin FIG. 8, as the plunger element 50 is advanced in the direction ofarrow A₁ toward the bladder 1140 in preparation for filling, thesingular check valve 82 in this embodiment allows air to escape frombehind the bladder 1140. As noted previously, duckbill check valves areexamples of one-way check valves that could be used in the plungerelement 50. Duckbill check valves offer the advantage of a self-cleaningsealing surface as well as a built-in flange for sealing the path aroundthe valve. Reverse or proximal movement of the plunger element 50 in thedirection of arrow A₂ in FIG. 9 creates a vacuum in this space. Thisvacuum pressure acts upon the cap-bladder assembly 100 to fill thebladder 1140 of this assembly 100 with a desired injection fluid. Oncefilled with a desired amount of injection fluid, subsequent forward ordistal operation of the piston element 14 of the fluid injector 12 inthe direction of arrow A₁ in FIG. 8 causes the injection fluid to bedispensed from the cap-bladder assembly 100.

Referring next to FIGS. 12-46, various embodiments and variations of thebladder syringe 20 are shown, as are numerous embodiments of the bladder1140 that are suitable for use in the cap-bladder assembly 100. Whilevarious embodiments and variations of the bladder syringe 20 along withnumerous embodiments of the bladder 1140 suitable for use in thecap-bladder assembly 100 are illustrated in FIGS. 12-46, these are notto be considered exhaustive and other configurations are possible withinthe scope and teachings of this disclosure. FIGS. 12-13 show theembodiment of the bladder 1140 described previously wherein the membraneportion 1146 includes a generally W-shaped central well portion 1148defined by a series of “convolutes” “C” or arcuate sections. Themembrane portion 1146 has a generally consistent or uniformcross-section and the central well portion 1148 generally defines anoverall “W” shape. FIGS. 13A-13B shows the bladder 1140 supported by theretainer ring 140 according to the concepts outlined previously. Withthe convoluted central well portion 1148 in the center of the membraneportion 1146 more material is available in the inner portion of themembrane portion 1146 when the bladder 1140 is filled, for example, tothe 200 ml fill mark. The convolutes of the central well portion 1148are identified with reference character “C”. If desired, an additionalconvolute (not shown) could be added to the outer edge of the bladder1140 inward of the outer rib 1142 so that extra material is availablenear the interior wall 36 of the cylindrical body 30 and delay when thestretching of the bladder 1140 begins. FIG. 12A further shows that thetop or distal side 1150 may have lines, grooves, or markings 1100 whichprovide a visual indication to attendant medical personnel of thebladder 1140 being filled with fluid and in a stretched state. Thelines, grooves, or markings 1100 may be radial, circular, or have anysuitable orientation to visually alert a user. Such markings 1100 may beapplied to any of the embodiments of the bladder 1140 within thisdisclosure, and may be disposed on the bottom or proximal side 1152 aswell. FIGS. 12C-12D show that a reinforcing mesh or screen 1153 may beapplied to the innermost convolute C on the top side of the membraneportion 1146 to reinforce this convolute and to interact with the flatnub 139 on the distal portion 52 of the plunger element 50 discussedpreviously in connection with FIG. 10A. The mesh or screen 1153reinforces the weakest portion of the bladder 1140 and may be cottonfabric, aramid fiber, polyester fiber, and other similar materials, andmay also be stiffer material, like TPE, over-molded onto the innermostconvolute C.

FIGS. 14A-14B show an embodiment of the bladder 1140 that has a membraneportion 1146 that is substantially flat or planar and, thus, thisembodiment of the bladder 1140 is non-orientation specific. Thisembodiment is akin to a flat trampoline and may have the advantage ofbeing installed over a plunger element 50 disposed near or projectingfrom the distal end 32 of the cylindrical body 30 so that it protrudesfrom the cylindrical body 30. In this configuration, the bladder 1140may be placed over the distal portion 52 of the plunger element 50 sothat the center or tip of the plunger element 50 would contact thebladder 1140 first as the bladder 1140 is installed and, thereby, air isforced out from between the plunger element 50 and the bladder 1140,which could negate the need for the check valves 82 in the plungerelement 50.

FIGS. 15A-15B shows an embodiment of the bladder 1140 wherein themembrane portion 1146 has a centrally-located solid disc 1154 stacked onand a second solid disc 1156 each disposed centrally on the membraneportion 1146. One or both of the top or distal side 1150 and the bottomor proximal side 1152 of the membrane portion 1146 may have theforegoing solid discs 1154, 1156. Due to the presence of the solid discs1154, 1156, it will be appreciated that the membrane portion 1146exhibits a non-uniform cross-section in this embodiment. In thisembodiment, there is thicker material in the center of the bladder 1140,particularly the inner one-third (⅓) of the membrane portion 1146. Inuse, this inner one-third area formed by the solid discs 1154, 1156 isstretched very thin because the outer two-thirds is “vacuumed” to theinterior wall 36 of the cylindrical body 30 and contributes little tothe stretch. A thicker wall section in the inner one-third area, aspresent in this embodiment, provides a bladder 1140 with less stress athigher fill volumes and able to deliver fluid under high pressure.

FIGS. 16A-16B show an embodiment of the bladder 1140 with a membraneportion 1146 having a centrally-located solid ring 1158. One or both ofthe top or distal side 1150 and the bottom or proximal side 1152 of themembrane portion 1146 may have the foregoing solid ring 1158. Due to thepresence of the solid ring 1158, it will be appreciated that themembrane portion 1146 exhibits a non-uniform cross-section in thisembodiment. In this embodiment, the annular solid ring 1158 in thecenter of the bladder 1140 contributes to the stretching and filling ofthe bladder 1140. The embodiment of FIGS. 16A-16B is one of severalembodiments in this disclosure that comprise additional material in thecenter area of the membrane portion 1146 so that, for example, there isan interaction between the distal circular recess 138 and ledge 139 ofthe plunger element 50 in FIGS. 10A-10B to maintain the bladder materialaligned in the cylindrical body 30 during expansion/elongation of thebladder 1140 and thereby enables greater stretching or filling of thebladder 1140; any of the embodiments of the bladder 1140 having extracenter material may have this interaction feature.

FIGS. 17A-17B illustrate an embodiment of the bladder 1140 having amembrane portion 1146 that includes a W-shaped central well portion1160. The raised central well portion 1160 has a flat or planar topportion 1162 and a tapering sidewall 1164 leading to an annular outerconvolute 1165. The membrane portion 1146 has a generally uniformthickness or cross-section in this embodiment. The “top hat” profile inthis embodiment adds material in only one convolute 1165. By adding theconvolute 1165 toward the outside radius the area increases quickly bythe square of the radius.

FIGS. 18A-18B illustrate an embodiment of the bladder 1140 having amembrane portion 1146 with a similar W-shaped central well portion 1160to that shown in FIGS. 17A-17B but further includes a thickened centralportion 1166 which may be considered to be formed by two stacked discportions 1168, 1170 provided on opposing sides 1150, 1152 of themembrane portion 1146. Due to the presence of the thickened centralportion 1166, the membrane portion 1146 has a non-uniform cross-sectionin this embodiment. Extra material in the center of the membrane portion1146 along with the inclusion of a single outer convolute 1165 providesextra material in the center for dispersion to the interior wall 36 ofthe cylindrical body 30 and greater fill volumes.

FIGS. 19A-19B illustrate an embodiment of the bladder 1140 having amembrane portion 1146 with a series of radially-directed hollow bulbousportions that define radial convolutes 1172 formed as part of themembrane portion 1146 and which extend upward from the top or distalside 1150 of the membrane portion 1146. The radial convolutes 1172increase the surface area of the membrane portion 1146 from the centeroutward. The width of the individual radial convolutes 1172 may be wideras they approach the center of the membrane portion 1146 to provide morematerial toward the center of the membrane portion 1146.

FIGS. 20A-20B illustrate an embodiment of the bladder 1140 having amembrane portion 1146 with a series of concentric friction ribs 1174formed on the membrane portion 1146. One or both of the top or distalside 1150 and the bottom or proximal side 1152 of the membrane portion1146 may have the foregoing concentric ribs 1174. Due to the presence ofthe concentric ribs 1174 on the membrane portion 1146, the membraneportion 1146 has a non-uniform cross-section in this embodiment. Thefriction ribs 1174 resist sliding down the plunger element 50 andincrease friction to slow expansion of the bladder 1140 along theplunger 550 and retain the thickness of the membrane portion 1146 for alonger period of time during expansion. If the concentric friction ribs1174 are formed on the bottom or proximal side 1152 of the membraneportion 1146, the distal portion 52 of the plunger element 50 may haveopposing annular grooves to engage or interact with the concentricfriction ribs 1174.

FIGS. 21A-21B illustrate an embodiment of the bladder 1140 in which themembrane portion 1146 has a central “wagon wheel” formation 1176surrounded by outer concentric solid rings 1178. The wagon wheelformation 1176 includes a central raised disc 1180 and a series ofradial spokes or ribs 1182 extending outward from the central raiseddisc 1180. An inner concentric solid ring 1184 extends concentricallyabout the central raised disc 1180 to intersect the various radialspokes or ribs 1182. One or both of the top or distal side 1150 and thebottom or proximal side 1152 of the membrane portion 1146 may have theforegoing wagon wheel formation 1176 surrounded by the outer concentricsolid rings 1178. The radial ribs 1182 that extend from the center ofthe membrane portion 1146 add stiffness to the bladder 1140 in thisembodiment and retard stretch of material to the interior wall 36 of thecylindrical body 30. Material from the radial ribs 1182 could also bespread out circumferentially to help maintain a minimum thickness of themembrane portion 1146 at extended fill volumes.

FIGS. 22A-22B illustrate an embodiment of the bladder 1140 in which themembrane portion 1146 is folded and twisted like a “Jiffy Pop®” popcornfolded aluminum foil lid The twisted and folded membrane portion 1146could be on the top side 1150 and/or the bottom side 1152, and byapplying a vacuum, the bottom side 1152 could pull down and the top side1150 expand up. In the present embodiment, the material comprising thebladder 1140 may not have to be resiliently elastic. For simplicity, thedetails of the outer circumferential rib 1142 and radially-inwardextending portion 1144 are omitted in FIGS. 22A-22B.

FIGS. 23A-23B illustrate an embodiment of the bladder 1140 having aseries of concentric angular-shaped convolutes 1186 in the membraneportion 1146. The use of a series of concentric convolutes 1186,generally triangular-shaped convolutes 1186, increases the surface areaof the bladder material. For simplicity, the details of the outercircumferential rib 1142 and radially-inward extending portion 1144 areomitted in FIGS. 23A-23B.

FIGS. 24A-24B illustrate an embodiment of the bladder 1140 in which themembrane portion 1146 is shaped like a flat trampoline with a thinnersection 1190 in the center and a thicker outer section 1192 taperingfrom the thinner center section 1190. The thicker outer section 1192 onthe outside of the membrane portion 1146 provides more material forstretching of the bladder 1140 and the thinner inner or center section1190 creates more stress to cause the thicker outer section 1192 tocontribute more to the expansion of the bladder 1140 during operation.For simplicity, the details of the outer circumferential rib 1142 andradially-inward extending portion 1144 are omitted in FIGS. 24A-24B.

FIGS. 25A-25B illustrate an embodiment of the bladder 1140 in which themembrane portion 1146 has a flat trampoline center section 1194 in thecenter and two outer concentric ribs 1196. The outermost rib 1196 mayoptionally form the circumferential edge of the bladder 1140 and thusnecessitate a change in the shape of the circumferential recess orgroove 126 in the cap body 104 which secures the bladder 1140 therein,and a corresponding change in the shape defined by the radial and axialflange 142, 144 of the retainer ring 140. Alternatively, the details ofthe outer circumferential rib 1142 and radially-inward extending portion1144 could be included in the membrane portion 1146 of this embodiment,outward from the outermost rib 1196. FIGS. 26A-26B illustrate avariation of the embodiment shown in FIGS. 25A-25B wherein a pluralityof concentric ribs 1196 is provided outward from the flat trampolinecenter section 1194. For simplicity, the details of the outercircumferential rib 1142 and radially-inward extending portion 1144 areomitted in FIGS. 26A-26B.

FIGS. 27A-27B illustrate an embodiment of the bladder 1140 in which themembrane portion 1146 has a series of thicker wall sections 1198 nearthe center of the bladder 1140, with the inner most wall section 1198having the thickest cross-section. This embodiment allows for morematerial to be available in the center as the membrane portion 1146 isextended. The wall thickness increase could be a gradual transitionrather than the shown stepped configuration. For simplicity, the detailsof the outer circumferential rib 1142 and radially-inward extendingportion 1144 are omitted in FIGS. 27A-27B.

FIGS. 28A-28B illustrate an embodiment of the bladder 1140 in which themembrane portion 1146 defines a central well portion 1200 connected toan outer rim 1202 by a series of frangible webs 1204 that retard therelease of bladder material to the interior wall 36 of the cylindricalbody 30. Since the webs or ribs 1204 are frangible and tear away after acertain strain is achieved, the bladder 1140 in this embodiment is aone-time use component. For simplicity, the details of the outercircumferential rib 1142 (connected to the outer rim 1202) andradially-inward extending portion 1144 are omitted in FIGS. 28A-28B.

FIGS. 29A-29B illustrate an embodiment of the bladder 1140 in which themembrane portion 1146 has a second material molded-in or adhered to theoutside surface to reduce the sliding along the plunger element 50. Thismaterial could have a higher coefficient of friction and could befriction bands 1206 around the membrane portion 1146, or could be in theform of friction bands 1206 provided on the bottom side 1152 of themembrane portion 1146 as illustrated. For simplicity, the details of theouter circumferential rib 1142 and radially-inward extending portion1144 are omitted in FIGS. 29A-29B.

FIGS. 30A-30B illustrate an embodiment of the bladder 1140 in which themembrane portion 1146 has extra material 1208 on the outsidecircumference. This extra material 1208 is rolled-up like a condominstead of having one or more convolutes. The extra material 1208unrolls as a vacuum draws the bladder 1140 like a rolling diaphragm.There may be a thicker section of material (not shown) in the center ofthe membrane portion 1146 to allow for additional stretch at extendedfill volumes of the bladder 1140. For simplicity, the details of theouter circumferential rib 1142 and radially-inward extending portion1144 are omitted in FIGS. 30A-30B.

FIGS. 31A-31B illustrate an embodiment of the bladder 1140 in which themembrane portion 1146 is composed of two or more materials. One materialcould be, for example, polypropylene to reduce friction. Additionally,the membrane portion 1146 could have over-molded ribs 1210 on the bottomside 1152 of the bladder 1140 that help keep the bladder 1140 fromsticking to the interior wall 36 of the cylindrical body 30. Theseover-molded ribs 1210 are operable to lift the bladder 1140 off theinterior wall 36 because they are raised surfaces, and may be made of amaterial with a low coefficient of friction, such as polypropylene, toenable the bladder 1140 to stretch down the interior wall 36. Theover-molded ribs 1210 do not have to be continuous and could be shortsegments as illustrated to allow the bladder 1140 freedom to stretch inall directions. For simplicity, the details of the outer circumferentialrib 1142 and radially-inward extending portion 1144 are omitted in FIGS.31A-31B.

FIGS. 32A-32B illustrate a clam-shaped embodiment of the bladder 1140.In this embodiment, the membrane portion 1146 is shaped like a clam withan undulating surface texture 1212 that creates more surface area for aconstrained diameter. This membrane portion 1146 may have a uniform wallthickness or varying wall thickness. For simplicity, the details of theouter circumferential rib 1142 and radially-inward extending portion1144 are omitted in FIGS. 32A-32B.

FIGS. 33A-33B illustrate an embodiment of the bladder 1140 in which themembrane portion 1146 has a non-symmetric cross-section such as formedby interlinked hourglass shaped sections or beads 1214 with repeatedthick and thin sections/beads. For simplicity, the details of the outercircumferential rib 1142 and radially-inward extending portion 1144 areomitted in FIGS. 33A-33B.

FIGS. 34A-34B illustrate an embodiment of the bladder 1140 in which themembrane portion 1146 has a flat trampoline center section 1216 in thecenter and a series or plurality of stepped and radially-extending ribsor spokes 1218 extending outward from the center section 1216 to theouter circumferential rib 1142. The stepped and radially-extending ribsor spokes 1218 may be provided on the bottom or proximal side 1152 ofthe membrane portion 1146, as illustrated, or on both sides.

FIGS. 35A-35B show an embodiment of the bladder 1140 similar to thebladder 1140 shown in FIGS. 34A-34B. In the embodiment shown in FIGS.35A-35B, the bottom side 1152 of the membrane portion has a flattrampoline center section 1220 in the center and a series or pluralityof concentric stepped or ridged portions 1222 around the center section1220. These concentric stepped or ridged portions 1222 may be adapted tocooperate with corresponding concentric stepped or ridged portions 1224on the surface of the distal portion 52 of the plunger element 50. Inthis embodiment, material is present in the center of the bladder 1140in the unstretched state. Thicker material is present due to the steppedincreases in the thickness toward the center of the membrane portion1146 and the stepped or ridged portions 1224 on the plunger element 50are disposed to cooperatively engage the corresponding concentricstepped or ridged portions 1222 to retard the distribution of thebladder material to the interior wall 36 of the cylindrical body 30. Asthe steps or ridges 1222 lock on the steps or ridges 1224 on the distalportion 52 of the plunger 550, the bladder material will be pulled untilthe strain on the bladder 1140 causes the material to thin in the areaof the ridge 1224 and it will be released and a new transition orportion will slide down until it “locks” onto the subsequent plungerridge 1224 until the steps or ridges 1222 ultimately disappear as thebladder 1140 is filled and stretched. The plunger element 50 may havemultiple steps or ridges 1224 or only require a singular step or ridge1224 toward the outside radius thereof.

Referring next to FIG. 36, vertical grooves 1226 may be provided on theinterior wall 36 of the cylindrical body 30 to desirably reduce slidingfriction between the bladder 1140 and the interior wall 36 and allow thebladder 1140 to slide more easily along the interior wall 36. Thevertical grooves 1226 are operable to lift the bladder 1140 off theinterior wall 36 because they reduce the area in surface contact betweenthe bladder 1140 and the interior wall 36. While vertical grooves 1226are shown in FIG. 36, it is possible to modify the surface finish of theinterior wall 36 in other ways to reduce the amount of surface areacontact between the bladder 1140 and the interior wall 36. Thismodification could be done when molding the cylindrical body 30, such asproviding the interior wall 36 with straight groove lines, as shown,adding a roughened surface finish, or adding vertical ribs alonginterior wall 36 of the cylindrical body 30.

Referring to FIG. 37, an embodiment of the bladder 1140 is shown inwhich the membrane portion 1146, or body of the bladder 1140, is in theform of a rolling diaphragm 1228. In FIG. 37, the plunger element 50,cylindrical body 30, and cap-bladder assembly 100 of the bladder syringe20 are shown schematically, and details of the connection/interactionbetween these elements are omitted but may be similar to that shown inFIGS. 1-2. The rolling diaphragm 1228 is longer in the axial directionin the bore 37 of the cylindrical body 30 and is adapted to fold overonto itself. The plunger element 50 operates as a displacement plungerand does not seal against the interior wall 36 of the cylindrical body30, and is sized to provide a small annular clearance area between theplunger element 50 and the interior wall 36 of the cylindrical body 30on the order of two thicknesses of the rolling diaphragm 1228. Therolling diaphragm 1228 may be resiliently elastic or may be not bestretchable in this embodiment. If the rolling diaphragm 1228 is notstretchable, then the rolling diaphragm 1228 is desirably about half thelength of the cylindrical body 30.

Referring to FIG. 38, in this embodiment the bladder 1140 has a membraneportion 1146, or body, of the bladder 1140, that is molded out of anon-fellable material, such as thin walled PET. In this embodiment, themembrane portion 1146, or body, of the bladder 1140 is shaped like anopen topped cylinder 1230. The walls of the bladder cylinder 1230 arecorrugated and folded like a bellows. In FIG. 38, the plunger element50, cylindrical body 30, and cap-bladder assembly 100 of the bladdersyringe 20 are shown schematically, and details of theconnection/interaction between these elements are omitted but may besimilar to that shown in FIGS. 1-2. The plunger element 50 has a largedistal disc portion 1232 to support a rigid bottom 1234 of the bladdercylinder 1230 and a fixed or inter-engaging connection may be providedbetween the bladder cylinder bottom 1234 and the disc portion 1232 toenable the plunger element 50 to operate the bladder cylinder 1230 inthe forward or distal and rearward or proximal directions in the bore 37of the cylindrical body 30. The bladder cylinder 1230 may be blow moldedin this embodiment and be in other shapes rather than cylindrical, suchas a diamond shape (e.g., polygonal).

Referring to FIGS. 39A-39B, an embodiment of the bladder 1140 has amembrane portion 1146, or body, of the bladder 1140, that is formed by acup-shaped distal portion 1236 and a depending rolled-up portion 1238.FIG. 39A shows an isolation view of the bladder 1140 according to thisembodiment, and FIG. 39B shows the bladder 1140 associated with theoverall bladder syringe 20. In FIG. 39B, the plunger element 50,cylindrical body 30, and cap-bladder assembly 100 of the bladder syringe20 are shown schematically, and details of the connection/interactionbetween the cup-shaped portion 1236 of the bladder 1140 and the cap body104 are omitted but may be similar to that shown in FIGS. 1-2. In use,air is removed from behind the bladder 1140 in this embodiment byadvancing the plunger element 50 until the shape of the bladder 1140 iscompletely flat in the cap body 104 and then the bladder 1140 is filledaccording to the general procedure described previously using vacuumpressure, which unfurls the depending rolled up portion 1238. Thebladder 1140 in this embodiment is stiff enough to expand withoutvacuum.

Referring next to FIG. 40, an embodiment of the bladder 1140 is shownthat is pulled down by operation of the plunger element 50 rather thanvacuum-operated. In this embodiment, the membrane portion 1146 is shapedlike an open cylinder with a rigid bottom portion 1240 and a flexiblesidewall 1242. If desired, the rigid bottom portion 1240 and flexiblesidewall 1242 may be integrally molded together and, further, the rigidbottom portion 1240, flexible sidewall 1242, and cap body 104 may all bemolded integrally together using co-injection molding techniques toarrive at the schematically illustrated embodiment shown in FIG. 40. Inoperation, the plunger element 50 is adapted with a connecting element1244 that is adapted to engage a corresponding connecting element 1246in the rigid body portion 1240 so that the rigid bottom portion 1240 andplunger element 50 become fixed together. During the reciprocal movementof the plunger element 50, in the directions of arrows A₁, A₂ describedpreviously, the flexible sidewall 1242 stretches based on the linearmovement of the plunger element 50. In FIG. 40, the plunger element 50,cylindrical body 30, and cap-bladder assembly 100 are shownschematically, and details of the connection/interaction between thecylindrical body 30 and the cap-bladder assembly 100 may be found in theforegoing.

In FIG. 41, an embodiment of the bladder 1140 is shown in which themembrane portion 1146 matches a tapered profile 1248 of the interiorcavity 106 of the cap body 104 and has an open end 1250 with a shortsidewall 1252. In this embodiment, the bladder 1140 nests into theinterior cavity 106 of the cap body 104 and is protected. In operation,the plunger element 50 (not shown in FIG. 41) is moved forward ordistally into the interior cavity to expel air out from between thedistal portion 52 of the plunger 550 and the bladder 1140 and is thendrawn backward to cause the bladder 1140 to fill with fluid. As theplunger element 50 retracts vacuum pressure is generated and themembrane portion 1146, which has the shape of the interior cavity 106 ofthe cap body 104, to enable the bladder 1140 to fill with fluid. In FIG.41, the cylindrical body 30 and cap-bladder assembly 100 are shownschematically, and details of the connection/interaction between thecylindrical body 30 and the cap-bladder assembly 100 may be found in theforegoing.

In FIGS. 42A-42B, an embodiment of the bladder 1140 is shown in whichthe membrane portion 1146 is provided in the form of a flexible bodythat has an outer diameter to fit within the inner diameter of thecylindrical body 30, and the cap body 104 is molded as a solid planarend cap that is adapted to seat onto a planar top rim 45 of thecylindrical body 30. Additionally, the flexible body has a sideconnector 1254, which is illustrated as a luer connector for connectionto a fluid container or tubing set, as examples. The bladder 1140 may beof two-piece construction in which the side connector 1254 is molded ofa different material than the flexible cylindrical bladder 1140. Forexample, the side connector 1254 may be co-injection molded with theflexible bladder 1140 yielding a unitary structure as illustrated inFIGS. 42A-42B. Once the flexible bladder 1140 is placed in thecylindrical body 30, the plunger element 50 (not shown) is moved forwardor distally to expel air out from the flexible bladder 1140 via the sideconnector 1254, and withdrawal of the plunger element 50 draws a vacuumin the cylindrical body 30 and fluid enters the flexible bladder 1140via the side connector 1254.

Referring to FIGS. 43A-43C, another embodiment of the bladder syringe 20is shown that incorporates a dual vacuum plunger element 50. In thisembodiment, the bladder 1140 has the general configuration of thebladder syringe 20 shown in FIGS. 12A-12B with the membrane portion 1146having a general W-shaped convoluted central well portion 1148 so thatextra material is present in the center of the membrane portion 1146 toallow for slow release of material to the interior wall 36 of thecylindrical body 30. The dual vacuum plunger element 50 comprises anouter plunger element 152 surrounding an inner plunger element 154, withthe inner plunger element 154 being movable relative to the outerplunger element 152. The inner plunger element 154 comprises a conicaldistal portion 156 generally shaped to engage the center of the W-shapedconvoluted central well portion 1148 of the bladder syringe 20, asgenerally shown in FIG. 43A, and a cylindrical proximal portion 158. Aninternal vent 159 extends interiorly within the cylindrical portion 158from the circumferential exterior of the cylindrical portion 158 to aproximal end 160 of the cylindrical portion 158. The proximal end 160 ofthe cylindrical portion 158 is provided with engagement tabs 161 forengagement with the piston interface tip 16 of the piston element 14 ofthe fluid injector 12 shown in FIG. 7, discussed previously. Inoperation, air is expunged from between the bladder 1140 and the capbody 104 by advancing the dual plunger element 50, in the assembledstate shown in FIG. 43A, forward so that the conical distal endpresented by the assembled dual plunger element 50 seats in the interiorcavity 106 of the cap body 104 in a similar manner to the operation ofthe bladder syringe 20 discussed previously. The internal vent 159permits air to be vented from the bore 37 of the cylindrical body 30distal or forward of the dual plunger element 50 as the dual plungerelement 50 is advanced.

In the present embodiment, when it is desired to fill the bladdersyringe 20, the inner plunger element 154 retracts first relative to theouter plunger element 152, as shown in FIG. 43B, thereby closing theinternal vent 159 and drawing in the loose material of the convolutedcentral well portion 1148 of the bladder syringe 20 into an annularspace 162 defined by the outer plunger element 152 wherein the innerplunger element 154 is located, as shown in FIGS. 43B-43C. At thispoint, the outer plunger element 152 also engages or contacts thebladder 1140. In FIG. 43C, the cylindrical portion 158 of the innerplunger element 154 seats against a shoulder 164 defined by the outerplunger element 152 in the annular space 162 and both the outer plungerelement 152 and the inner plunger element 154 thereafter retracttogether. As the plunger elements 152, 154 retract and the bladder 1140fills with fluid, and the bladder material in contact with the outerplunger element 152 is drawn out first followed by the loose material atthe center of the W-shaped convoluted central well portion 1148 incontact with the inner plunger element 154. Once the bladder 1140 isfilled with fluid to the desired volume, the plunger elements 152, 154may be advanced together by the piston element 14 of the fluid injector12 shown in FIG. 7. A mechanical pre-stretch of the bladder 1140 couldalso be performed before operation of the dual plunger element 50 in theforegoing manner. In FIGS. 43B-43C, the connection between thecap-bladder assembly 100 and the cylindrical body 30 is shownschematically. In summary, in the embodiment shown in FIGS. 43B-43C, aco-axial dual plunger element 50 is used to generate a vacuum. As thedual plunger element 50 moves forward, the interior vent 159 is openallowing the air between the bladder 1140 and the piston dual plungerelement 50 to escape. When the piston element 14 of the fluid injector12 draws the dual plunger element 50 back, the inner plunger element 154withdraws into the outer plunger element 152 closing and sealing theinternal vent 159 in the inner plunger element 154 and creating avacuum. The co-axial dual plunger element 50 pulls bladder material intothe center as the annular space 162 is formed or opens between the innerand outer plunger elements 154, 152 to keep the bladder 1140 in acorrect position for filling.

Referring to FIGS. 44A-44B, another embodiment of the bladder syringe 20is shown that incorporates a cylindrical body 30, plunger element 50,cap body 104, and bladder 1140 each set an angle to allow for moresurface area of contact between the bladder 1140 and plunger element 50.In these figures, the plunger element 50, cylindrical body 30, and capbody 104 of the bladder syringe 20 are shown schematically, and detailsof the connection/interaction between these elements are omitted but maybe similar to that shown in FIGS. 1-2. In this embodiment, the distalend 32 of the cylindrical body 30 and a distal plunger head 166 of theplunger element 50 define corresponding obtuse angles with a horizontalplane H, and the cap body 104 is formed to match the angular shape ofthe distal end 32 of the cylindrical body 30. The bladder 1140 comprisesa planar membrane portion 1146 but the membrane portion defines the sameangle as the foregoing components between the circumferential rib 1142.This angular orientation allows more bladder material to be stretched asthe angled plunger element 50 is withdrawn in the cylindrical body 30during filling of the bladder 1140. The bladder 1140 is also placed atan obtuse angle to the interior wall 36 of the cylindrical body 30, asopposed to perpendicular as in previous embodiments, and this obtuseangle provides a greater surface area for contact between the bladder1140 and plunger element 50, and the angular orientation increases thesurface area of available bladder material as well as the surfacecontact area with the plunger element 50. The greater contact surfacearea means less strain on the bladder 1140 as it is stretched toextended fill volumes. The distal plunger head 166 of the plungerelement 50 is generally shaped to accommodate this obtuse angle, andcould also be square or round depending on the cross-sectional shape ofthe cylindrical body 30, which need not be horizontal and circular incross-section in this embodiment. A further alternative for thisembodiment mounts the bladder 1140 at an obtuse angle but is provided tohave a shape to match the conical interior cavity of the conical capbody 104 shown in previous embodiments. In FIGS. 44A-44B, the connectionbetween the cap-bladder assembly 100 and the cylindrical body 30 isshown schematically.

Referring to FIGS. 45A-45B, another embodiment of the bladder syringe 20is shown schematically in which the cap body 104 and bladder 1140 arebreach-loaded into the bore 37 of the cylindrical body 30. Prior to use,the cap body 104 and bladder 1140 may be disposed in the bore 37 of thecylindrical body 30 at the proximal end 34 of the cylindrical body 30.In this embodiment, the distal end 32 of the cylindrical body 30 may beconical-shaped and define a distal opening 168. The plunger element 50has a plunger head 170 that is shaped to match the interior shape of thecap body 104, and the plunger element 50 is used to move the cap body104 and the bladder 1140 forward in the bore 37 of the cylindrical body30. The cap body 104 further comprises a locking rim 172 on thedischarge conduit 110 that is adapted for engagement with the distalopening 168 so that when the plunger element 50 moves the cap body 104and bladder 1140 forward to the conical distal end 32 of the cylindricalbody 30, the discharge conduit 110 passes through the distal opening 168and the cap body 104 eventually locks onto the conical shaped distal end32 of the cylindrical body 30 via the locking rim 172. One of thelocking rim 172 and distal opening 168 is desirably capable of a certaindegree of resilient flexure, such as providing resilient flexiblesegments in the distal end 32 of the cylindrical body 30 that define thedistal opening 168, so that the locking rim 172 may pass through thedistal opening 168 and engage and lock onto the conical distal end 32 ofthe cylindrical body 30. The distal or forward movement of the plungerelement 50 to lock the cap body 104 to the distal end 32 of thecylindrical body 30 also expel air from the space between the bladder1140 and the cap body 104 via the discharge conduit 110. When theplunger element 50 is withdrawn in the cylindrical body 30, the bladder1140 is stretched under vacuum pressure in the manner discussedpreviously and filled with fluid while the cap body 104 remainsconnected to the distal end 32 of the cylindrical body 30. The bladder1140 is extended when the plunger head 170 of the plunger element 50 isadvanced into interior cavity 106 of the cap body 104.

Referring to FIGS. 46A-46C, another embodiment of the bladder syringe 20is shown schematically and comprising a dual diaphragm arrangement 174which is driven by a fluid displacement actuator 176. In thisembodiment, a syringe body 178 is provided having a closed distal end180 and an open proximal end 182. The distal end 180 has a dischargeport 184 with an end connector. The proximal end 182 of the syringe body178 is adapted for a releasable fixed connection with the fluiddisplacement actuator 176, such as may be found in the Medrad, Inc.patents discussed previously, which describe interfacing features forsecuring a Stellant® CT syringe to a Stellant® fluid injector. The fluiddisplacement actuator 176 comprises an open interfacing end 186 toaccept and connect to the proximal end 182 of the syringe body 178, andfurther comprises a pressurization port 188 for connection to a fluidpressurizing source used to pressurize the fluid displacement actuator176. A reusable bladder 190 is provided in the fluid displacementactuator 176 and is adapted to drive a disposable bladder 192 thatcovers the proximal end 182 of the syringe body 178. The syringe body178 and attached disposable bladder 192 form the single-use disposableportions of the dual diaphragm system 174 of this embodiment. Thedisposable bladder 192 may be co-injection molded to the open proximalend 182 of the syringe body 178. As shown in FIGS. 46B-46C, as the fluiddisplacement actuator 176 is pressurized, the disposable bladder 192 isdriven by the reusable bladder 190 to alternately fill the syringe body178 with fluid and dispense fluid therefrom.

In use, FIG. 46A shows the disposable bladder 192 and the reusablebladder 190 in an equilibrium state prior to pressurization of the fluiddisplacement actuator 176. In FIG. 46B, the fluid displacement actuator176 is pressurized with fluid, for example compressed air or a hydraulicfluid, and thus the reusable bladder 190 expands against the disposablebladder 192. FIG. 46C shows the bladder syringe 20 at the end of a fluidinjection wherein fluid in syringe body 178 in the area distal ofdisposable bladder 192 is discharged via discharge port 184.

The numerous foregoing shapes of the bladder 1140 provide variousembodiments with different characteristics in the way the material ofthe bladder 1140 is distributed to the interior wall 36 of thecylindrical body 30 during operation of the bladder syringe 20 with thefluid injector 12. The provision of more material in the center of themembrane portion 1146 slows the release of the bladder 1140 to theinterior wall 36 of the cylindrical body 30 during withdrawal operationof the plunger element 50 in the bladder syringe 20, as is provided byone or more of the embodiments of the bladder 1140 discussed previously.The provision of more central material generally reduces stress andstrain in the bladder 1140 during elongation, up to a point where theextra material becomes too thick to expand/elongate easily. Inparticular, adding curvature or convolutes C to the membrane portion1146, such as the embodiment shown in FIGS. 12-13, as an example,reduces stress and strain in the bladder 1140 during elongation.

Suitable materials for the bladder 1140 include any material that wouldpermit a substantially maximum fill of the bladder 1140 and this entailsan elongation of the bladder 1140 of between about 800-1800%. A lowmodulus (15-30 psi at 300% elongation) is also desirable for filling ofthe bladder 1140 by reducing the amount of vacuum required to expand thebladder 1140 during filling. Thermoplastic Elastomer (TPE) is onesuitable and preferred choice for the bladder 1140. This material can beclear or translucent, can have an elongation of over about 1400% with alow modulus/durometer, and can be injection molded. Thermoplasticelastomer (SBS rubber in olefinic matrix) has been demonstrated to workwell for the bladder 1140, has successfully reached an 1800% elongation,has a low modulus/durometer, and can be injection molded. Silicone,urethane, and polyisoprene (natural or synthetic) are also suitablechoices of materials for the bladder 1140. A material with clarity forair bubble detection is also desirable and this requirement is met bythe foregoing materials. Further, while mentioned in connection withcertain embodiments, it is also possible within the teachings of thisdisclosure to eliminate the use of the retainer ring 140 and have thebladder 1140 co-injection molded with the cap body 104, with the capbody 104 and bladder 1140 being formed of different materials.

It is desirable in accordance with this disclosure to co-injection moldthe bladder 1140 to the cap body 104 of the cap 102, which wouldeliminate the need for the retainer ring 140. Typically, the cap body104 of the cap 102 is molded from a rigid thermoplastic material likepolyester and, without removing the cap body 104 from the molding tool,the bladder 1140 may be over-molded to the cap body 104. As discussed inthe foregoing, the bladder 1140 may be made of soft, highly elasticmaterial, such as TPE, that is molded directly onto the cap body 104.The formed cap body 104 with attached bladder 1140 is ejected from themolding tool as one component with no further assembly required. In theforegoing process, the TPE (or any bladder material described herein) isinhibited from forming a chemical bond with the interior of the cap body104 by providing suitable surface texturing in the interior cavity 106,by appropriate material selection for the bladder 1140 and the cap body104, and/or by applying anti-bonding agents between the cap body 104 andthe bladder 1140; typically only vacuum pressure is available accordingto most embodiments described herein to “pull” the bladder 1140 outwardfrom the cap body 104 and fill the bladder syringe 20 with fluid.Molding the bladder 1140 with the cap body 104 provides benefits of lowmanufacturing cost and lower particulate formulation, and eliminates theneed to manually assemble the bladder 1140 to the cap body 104.Additionally, the sterilization cycle time may be reduced. Nonetheless,this disclosure also includes the option of sterile molding of the capbody 104 separate from the bladder 1140, which allows greaterflexibility in the design and shape of the bladder 1140 as the bladder1140 no longer needs to follow the shape of the cap body 104, and thisvariation includes use of the retainer ring 140. Furthermore, thebladder 1140 may be over-molded onto the retainer ring 140 which is theninserted into the interior cavity 106 of the cap body 104 of the cap102, (see the arrangement shown in FIGS. 13A-13B as an example). Theretainer ring 140 provides a rigid frame to support the bladder 1140 andcan isolate the bladder 1140 from assembly torque during installation ofthe cap-bladder assembly 100 on the cylindrical body 30. In yet afurther molding method, the cap body 104 and bladder 1140 may beco-injection molded and use still a retainer ring 140 to support thebladder 1140 in the interior cavity 106 of the cap body 104 of thecap-bladder assembly 100.

As an alternative in the foregoing over-molding process, as shown inFIG. 47A, the bladder 1140 may be co-injection molded with a thin innerliner 194 that fits within a reusable cap body 104 that cooperates withthe cylindrical body 30 in the manner described previously, andeliminates the need for the retainer ring 140. Thus, in this variation,the bladder 1140 is over-molded to the inner liner 194, which may bemade of polypropylene or any other of the plastic materials detailedpreviously in connection with the cap body 104. Again, the bladder 1140is prevented from forming a chemical bond with the interior of the innerliner 194. In this embodiment, the cap body 104 comprises a dischargeconduit 110 and the inner liner 194 also includes a discharge conduit196 that fits within the discharge conduit 110. In FIG. 47A, the innerliner 194 has an exterior circumferential rim 424 that is molded to anexterior circumferential rim 1264 of the bladder 1140. Alternatively,the circumferential rims 424, 1264 may be secured by other means such asultrasonic welding, adhesive, and like joining methods. The exterior rim1264 on the bladder 1140 comprises a depending rib 1266 adapted forproviding a sealing engagement with the distal end or rim of thecylindrical body 30 in an embodiment of the bladder syringe 20 shown inFIGS. 71A-71C described herein.

While in FIG. 47A, the bladder 1140 is shown connected to the open endof the inner liner 194, the bladder 1140 may be molded to the innerliner 194 so as to wrap around the exterior of the inner liner 194 asshown in FIG. 47B and, thereby, may be able to form a surface seal 198against the interior wall of the cap body 104 in the interior cavity 106thereof. The inner liner 194 may be fitted into the interior cavity 106of the cap body 104 and held in the interior cavity 106 by a suitablefriction fit or snap fit connection, or a mechanical connection. Thebladder 1140 provides the surface seal 198 between the interior cavity106 of the cap body 104 and the inner liner 194. The cap body 104 mayfurther have a cylindrical section that extends beyond the bladder/linercombination that mechanically connects to the cylindrical body 30 anddoes not require a seal.

As a further alternative, as shown in FIG. 47C, the reusable cap 102 mayhave a cap body 104 with a co-injection molded bladder 1140, with themembrane portion 1146 having a central well portion 1268 surroundedcircumferentially by a circumferential region 1270, which may be taperedas illustrated. As shown in FIG. 47B, the distal side 1150 of themembrane portion 1146 generally conforms to the internal shape of theinterior cavity 106 of the cap body 104 and the opposing proximal side1152, including the central well portion 1268 and surrounding taperedarea or region 1270, defines a profile or shape that matches the profileof the distal portion 52 of the plunger element 50 as shown in FIG. 47C.Additionally, in FIG. 47C, an outer circumferential rim or flange 1272of the bladder 1140 comprises a pair of circumferential ribs 1274, 1276and an outer circumferential rim or flange 1278 of the cap body 104comprises a pair of depending circumferential ribs 1280, 1282 that areadapted to engage the upstanding ribs 1274, 1276, respectively, duringthe co-injection molding process. As an alternative, the cooperatingribs 1274, 1280 and 1276, 1282 may be joined by other bonding methodssuch as ultrasonic welding, laser welding, adhesive bonding, and liketechniques.

In FIG. 47D, the bladder 1140 is provided with a flexible bag-typemembrane body that is co-injection molded with a rigid discharge conduit196 that may seat within the discharge conduit 110 on the cap body 104of the cap 102, as schematically illustrated in this figure whichprovides just the schematic details of the bladder syringe 20.

Referring to FIGS. 47E-47F, when over-molding the bladder 1140 to thecap body 104 of the cap 102, as in the embodiment shown in FIG. 47C, asan example, it is desirable prevent the membrane portion 1146 fromsticking to the interior of the cap body 104. Thus, when a vacuum isgenerated in the cylindrical body 30 by action of the plunger element50, the bladder 1140 may be easily pulled from the interior cavity 106of the cap body 104 of the cap 102. However, it is also advantageous tohave the outer circumferential rim or flange 1272 of the bladder 1140fixed to the outer circumferential rim or flange 1278 of the cap body104 so that the bladder 1140 does not separate from the cap 102 duringshipping and handling. Also, it is also desirable to have the outercircumferential rim or flange 1272 of the bladder 1140 in solid contactor fixed with the outer circumferential rim or flange 1278 of the capbody 104 to prevent leaking during removal of the cap 102 from thecylindrical body 30 when fluid is present in the bladder 1140. In FIGS.47E-47F an embodiment is shown that illustrates that during theover-molding of the bladder 1140, bladder material may flow from belowthe cap body 104 and into a recess 1292 in the outer circumferential rimor flange 1278 of the cap body 104 through through-holes 1294 defined inthe outer circumferential rim or flange 1278, and this bladder materialmay reconnect with itself above the outer circumferential rim or flange1278 in the recess 1292. The bladder 1140 is then locked mechanically inthe regions between the through-holes 1294, with the added security of achemical bond as the bladder 1140 reconnects with itself. Additionalholes 1296 are shown in the bladder 1140 in FIG. 47E to illustrate wherethe material of the cap body 104 resides after the over-molding of thebladder 1140 to the cap body 104. FIG. 47E is an exploded view showingthe bladder 1140 and the cap body 104 after over-molding so thatmanufacturing details, such as the through-holes 1294 and the additionalholes 1296 may be viewed. The size, shape, and number of through holes1294 and the recess 1292 may vary as needed to strike a balance betweenbladder retention and injection mold tooling complexity and partmold-ability.

In yet another variation, the bladder 1140 may be made of soft, highlyelastic material, such as TPE, that is molded directly onto the retainerring 140 that is assembled into the cap body 104 in the manner describedpreviously in connection with FIGS. 13A-13B. The retainer ring 140provides a rigid frame to support the bladder 1140 and can isolate thebladder 1140 from assembly torque during installation of the cap body104 on the cylindrical body 30. The bladder 1140 and cap body 104 may bemade of any of the materials detailed previously in this disclosure andthe bladder 1140 is not limited to TPE as a choice of material. In thisvariation, it may also be possible to mold the retainer ring 140 and capbody 104 together as one component, wherein the retainer ring 140 andcap body 104 are connected together by, for example, a living hinge. Thebladder 1140 may then be co-injection molded to the retainer ring 140and all that is then required is to fold the retainer ring 140 into thecap body 104 (or vice versa) to complete the assembly of the bladder1140 to the cap body 104. In the foregoing, a dust cap may also beattached with a living hinge to the cap body 104 so that the dust capmay flip open or closed on the discharge conduit 110 and end connector112 like a flip top bottle lid, or the dust cap may be molded to betethered to the discharge conduit 110 of the cap body 104. Severalembodiments of a dust cap for the cap body 104 are described herein andmay have the foregoing living hinge or tethered connections to the capbody 104.

Referring further to FIG. 48, it is desirable to detect the presence ofthe cap-bladder assembly 100 on the cylindrical body 30 and/or thebladder 1140 in the cap body 104 of the assembly 100. For this purpose,as first shown in FIG. 48, a sensor 204 (in any of the forms discussedherein) may be provided coaxially in the plunger element 50 to determinewhether the cap body 104 and/or bladder 1140 is present on thecylindrical body 30. In the embodiment of the plunger element 50discussed in connection with FIG. 10A, the sensor 204 (in any of theforms discussed herein) may be disposed as part of the flat nub or ledge139 or, alternatively, be disposed in the distal circular recess 138 (asshown in FIG. 10A) that surrounds the flat nub or ledge 139. In FIG. 48,and FIG. 49 discussed herein, the cap-bladder assembly 100, cylindricalbody 30, and plunger element 50 are shown schematically to illustratevarious sensor arrangements and details of the cap-bladder assembly 100,cylindrical body 30, and plunger element 50 are found in the foregoing.The coaxial sensor 204 may be an optical sensor that detects presence ofthe bladder 1140 and/or the cap body 104 on the cylindrical body 30through the bladder 1140. In this embodiment, light is emitted from theoptical sensor 204 and reflected back to the sensor 204 when the bladder1140 is in place. The optical sensor 204 also may detect rupture of thebladder 1140 as fluid between the interface of plunger element 50 andthe bladder 1140 causes a change in optical properties that is sensed bythe optical sensor 204 (e.g., in the presence of air, no light isreflected back but in the presence of a liquid, light is reflectedback). In addition to the foregoing, all or part of the interior wall 36of the cylindrical body 30 and/or the plunger element 50 may be coatedwith a litmus coating that changes color in the presence of a liquid. Inthis variation, the optical sensor 204 may be adapted to identify thecolor change and send a signal indicating the presence of liquid in thecylindrical body 30 distal of the plunger element 50. As a furtheralternative, the membrane portion 1146 of the bladder 1140 and/orinterior wall 36 of the cylindrical body 30 or the plunger element 50may be coated with a color-changing chemical in the presence of liquid.If the bladder 1140 should leak or rupture, the color-changing chemical,similar to a dye-pack, changes color and this change is registered bythe optical sensor 204. The material comprising the bladder 1140 mayalso incorporate the color-changing dye chemical during manufacturing.Any of the optically determined sensed conditions may also be detectedby an external sensing device, such as external sensor device 260described herein in connection with FIGS. 57-58. Moreover, the coatingon the interior wall 36 of the cylindrical body 30, plunger element 50,or the bladder 1140 may be a chemical substance that generates gasbubbles, such as oxygen bubbles, in the presence of liquid that wouldchange the optical properties in the cylindrical body 30 sufficiently toenable the optical sensor 204 to register and send a signal to thecontroller of the fluid injector 12. The optical sensor 204 (or externalsensor device 260) may be a bubble detector as is known the medicalfield for detecting air bubbles in tubing.

In FIG. 48, the aforementioned full/partial litmus coating isrepresented as a litmus strip 205. Moreover, in the event of failure ofthe bladder 1140, leaking fluid will typically leak downward to theplunger element 50 and into the interior of the plunger element 50 viainterconnecting passages 64, 66 to reach the check valves 82 (see FIGS.1B and 4), and through the porous plug 134 (if present). The checkvalves 82 may be configured to create a low pressure drop so that, ifthe bladder 1140 breaks or leaks, the path of least resistance isthrough the check valves 82 and out the plunger element 50 into thefluid injector 12. The presence of fluid in the fluid injector 12 willbe immediately noticeable to attendant medical personnel, and a fluidsensor may also be located in the fluid injector housing 18 to detectfluid leakage into the housing 18.

As an alternative, the sensor 204 may be an ultrasonic sensor thatdetects the presence of the cap body 104 on the cylindrical body 30and/or detects the presence of the bladder 1140 in the cap-bladderassembly 100. The ultrasonic sensor 204 may further be used to detectwhether there is proper contact between the membrane portion 1146 of thebladder 1140 and the plunger element 50 during filling. In thisembodiment, sound waves are emitted from the ultrasonic sensor 204 andreflected back to the sensor 204 when the cap body 104 is in place. Theultrasonic sensor 204 also may detect rupture of the bladder 1140 asfluid between the interface of plunger element 50 and the bladder 1140causes a change in medium properties (air/vacuum to liquid) between theplunger element 50 and bladder 1140 that is sensed by the ultrasonicsensor 204. Moreover, the ultrasonic sensor 204 may also be used totrack the position of the bladder 1140 as it is being filled.

In addition to the foregoing, the sensor 204 in FIG. 48 may also be amechanical type sensor in which the body of the sensor 204 isspring-loaded to extend distally a short distance from the plungerelement 50 to the vicinity of the bladder 1140 when the cap body 104 isattached to the cylindrical body 30. Accordingly, as the cap-bladderassembly 100 is placed on the cylindrical body 30, the bladder 1140makes physical contact with the mechanical sensor 204 and depresses thesensor 204 which provides a signal that the cap-bladder assembly 100 ispresent. Thus, the bladder 1140 actuates the mechanical sensor 204during attachment of the cap-bladder assembly 100 and/or during fillingof the bladder 1140 when the bladder 1140 extends and makes contact withthe plunger element 50. In this embodiment, the mechanical sensor 204may further be able to determine volume or pressure in the extendedbladder 1140 when filled by the degree of physical contact between thebladder 1140 and the mechanical sensor 204. The mechanical sensor 204desirably has a large surface area head, such as by forming asubstantial portion of the distal portion 52 of the plunger element 50,and is backed by a spring with a low spring constant to avoid damage tothe bladder 1140 during use. Such a mechanical sensor 204 with a largesurface head may be found in U.S. Pat. No. 7,666,169 to Cowan et al. andis incorporated into a plunger element for a syringe; this patent ishereby incorporated herein by reference for this purpose. As analternative, the plunger element 50 may be spring-loaded to operate aspart of the mechanical sensor 204.

Furthermore, fluid dots (not shown) may be provided on the cylindricalbody 30 as an indicator of fluid within the bladder syringe 20. Suchfluid dots are well-known in the medical field, but because thecylindrical body 30 is intended to be reusable, in the presentembodiment, the fluid dots may be darkened or black fluid dots whenviewed in the presence of a liquid and would be immediately viewable byattendant medical personnel even from a distance.

Further, FIG. 49 illustrates a variation of the bladder syringe 20 shownin FIG. 48, wherein a vacuum tube 206 is connected to an external vacuumsource (not shown) and to a through-port 208 in the plunger element 50.This external vacuum source (not shown) may be used to fill the bladder1140. As an example, in use, an operator can position the plungerelement 50 at any desired axial position in the bore 37 of thecylindrical body 30 and apply a vacuum to draw the bladder 1140, insteadof using the seal of the plunger element 50 with the interior wall 36 ofthe cylindrical body 30 to create the vacuum.

As a further alternative, the sensor 204 in FIGS. 48-49 may furtherinclude, or alternatively be provided as, a fluid sensor 204 to detectany leakage of fluid from the bladder 1140 when filled with fluid, or afailure of the bladder 1140 such as a complete rupture thereof.Additionally, the coaxial sensor 204 in FIG. 49 may further include, oralternatively be provided as, a pressure sensor 204 that, in addition todetecting the presence of the bladder 1140, may be used to detect a leakin the bladder 1140 such as a partial or complete rupture thereof. Thechange in pressure in the cylindrical body 30 and physical separation ofthe bladder 1140 from the plunger element 50 is registered as a pressurechange in the cylindrical body 30 by the sensor 204. The fluid sensor204 may also be adapted to detect a trace chemical incorporated into themembrane portion 1146 of the bladder 1140 and/or on the interior wall 36of the cylindrical body 30 that is activated in the presence of aliquid. In the case of a leak or rupture of the bladder 1140, thechemical may be activated and sensed by the fluid sensor 204 whichprovides a signal to the controller of the fluid injector 12 regarding aleakage/failure situation involving the bladder 1140.

Referring to FIGS. 50-51, a pressure sensor 210 may be provided in theplunger element 50. In FIGS. 50-51, the cap-bladder assembly 100,cylindrical body 30, and plunger element 50 are shown schematically toillustrate various sensor arrangements and details of the cap-bladderassembly 100, cylindrical body 30, and plunger element 50 are found inthe foregoing. In one embodiment shown in FIG. 50, the pressure sensor210 is a pressure transducer that monitors or indicates vacuum pressurein the cylindrical body 30 distal or forward of the plunger element 50during filling of the bladder syringe 20 and communicates a signal tothe controller associated with the fluid injector 12. In anotherembodiment shown in FIG. 51, the plunger element 50 may further includea vacuum popette 212 that extends to the outer surface of the plungerelement 50 and actuates or moves when vacuum pressure is present in thecylindrical body 30 distal or forward of the plunger element 50 duringfilling of the bladder syringe 20. When this position change occurs, acoaxial sensor 214 disposed in the plunger element 50 registers orsenses movement of the popette 212. For example, the sensor 214 may beembodied as an optical sensor that measures a change in position of thepopette 212, which indicates the presence and level of vacuum pressure.The pressure sensor 210 may further make physical contact with thebladder 1140, as shown in FIG. 50, and the physical contact may registerthe pressure in bladder 1140 when air is expelled and no differentialpressure is present.

Referring to FIG. 52, a contact impedance measurement system 216 may beassociated with the plunger element 50 to determine the presence of thebladder 1140 and/or whether there is a leak in the bladder 1140 of thecap-bladder assembly 100, or a complete rupture of the bladder 1140.Such a system 216 may include placing conductive elements or strips 218on the distal portion 52 of the plunger element 50 which can detect thepresence of liquid on the distal portion 52 which completes anelectrical circuit between the conductive elements or strips or flexcircuits 218 and, thus, a leak or rupture of the bladder 1140. Leadwires 220 may be routed through the plunger element 50 to connect to acontroller associated with the fluid injector 12 so that leakage/ruptureof the bladder 1140 may be detected by the controller and furtheroperations involving the installed cap-bladder assembly 100 may behalted for replacement with a new cap-bladder assembly 100. Theconductive elements 218 are adapted to detect the sharp rise inconductivity or capacitance associated with fluid from a leaking orburst bladder 1140. In another embodiment, the conductive elements orstrips 218 may alternatively be electrical resistance sensors thatmeasure electrical resistance of the bladder 1140. Embedded conductiveparticles P, as shown in FIG. 52, or a thin, easily breakable ductilewire (not shown) may be provided within the membrane portion 1146 of thebladder 1140 during manufacturing that create varying resistancereadings depending on the amount of stretch as the particle densitydecreases with increased stretch. The electrical resistance elements orstrips 218 detect the varying resistance when the bladder 1140 isexpanded or contracted. The electrical resistance elements or strips 218may be used to determine several pieces of information and communicatethe same to the controller associated with the fluid injector 12. Thisinformation may include, for example, the amount of expansion or stretchof the bladder 1140 and, thus, fluid volume, the presence of the bladder1140, and/or vacuum pressure within the cylindrical body 30 forward ordistal of the plunger element 50. Furthermore, in case of a rupture ofthe bladder 1140, the electrical resistance element or strips 218 detectthe sharp change in conductivity or impedence associated with thestretching of the conductive particles or conductive wire or thebreakage of the conductive wire and register the same as a failure ofthe bladder 1140.

While the foregoing discussion provides the conductive elements, strips,or flex circuits 218 in association with the plunger element 50, thesemay be provided on the interior wall 36 of the cylindrical body 30 andwhich are embedded in the interior wall 36 to be flush. A suitableelectrical lead connection may pass through the cylindrical body 30 toconnect to the controller of the fluid injector 12. Furthermore, aradio-frequency identification (RFID) tag may be embedded into thematerial forming the bladder 1140 during manufacturing and, in the caseof a leak or rupture of the bladder 1140, the RFID tag may activate ordeactivate to indicate to the controller of the fluid injector 12alerting to the leak/rupture.

Referring to FIG. 53, a sensing arrangement is provided to mechanicallysense the presence of the cap-bladder assembly 100 on the cylindricalbody 30. In this embodiment, a long pin 222 is supported between thedistal and proximal ends 32, 34 of the cylindrical body 30. A sensorbase 224 is attached to the proximal end 34 of the cylindrical body 30and supports a mechanical sensor 226 that detects movement of the pin222. The pin 222 may be spring-biased toward the distal end 32 of thecylindrical body 30 by a spring 228 as shown. As the cap-bladderassembly 100 is attached to the distal end 32 of the cylindrical body30, the pin 222 is depressed against the mechanical sensor 226 by thecap body 104 of the cap-bladder assembly 100. The mechanical sensor 226registers the presence of the cap-bladder assembly 100 and sends asignal to the controller associated with the fluid injector 12. In FIG.53, the cap-bladder assembly 100 and cylindrical body 30 are shownschematically to illustrate various sensor arrangements and details ofthe cap-bladder assembly 100, cylindrical body 30, and plunger element50 are found in the foregoing.

Referring to FIG. 54, the bladder syringe 20 may have an external lightpipe assembly 230 for detecting the presence of a cap-bladder assembly100. The light pipe assembly 230 includes a light housing 232 having adistal end 234 and a proximal end 236 and carrying two light pipes 238,240 extending between the distal and proximal ends 234, 236. The lighthousing 232 is desirably molded as part of the cylindrical body 30 andextends axially along the cylindrical body 30, but also may be separatefrom the cylindrical body 30 and secured thereto by any desirablemechanical arrangement. The light housing 232 carries two light pipes238, 240 to carry light from a light emitter 242 and to a light receiver244, respectively. The cap body 104 includes a reflector element 246that extends radially outward from the cap body 104 to interface andconnect with the distal end 234 of the light housing 232. The reflectorelement 246 has a first reflector 248, typically a 45° reflector, whichdirects the light beam from the light emitter 242 and is carried by thelight pipe 238 across a gap 250 to a second reflector 252, typically a45° reflector, which directs the return light beam to the opposing lightpipe 240 which carries the light beam down the length of the lighthousing 232 to the light receiver 244. The presence of the cap body 104completes the light circuit and this information may be utilized by thecontroller associated with fluid injector 12 to confirm the presence andproper installation of the cap-bladder assembly 100 on the bladdersyringe 20. Proper installation of the cap-bladder assembly 100 on thebladder syringe 20 could also be accomplished by providing the lightpipe assembly 230 in such a manner that interruption of a light beam bythe cap body 104 would indicate the presence and proper installation ofthe cap-bladder assembly 100 on the bladder syringe 20. FIG. 55 shows avariation of the foregoing light pipe assembly 230 incorporatedintegrally into the sidewall of the cylindrical body 30 and referencemay be made to FIG. 54 for the details of the light pipe assembly 230.In FIG. 55, the cap-bladder assembly 100 and cylindrical body 30 areshown schematically to illustrate various sensor arrangements anddetails of the cap-bladder assembly 100, cylindrical body 30, andplunger element 50 are found in the foregoing.

Referring to FIG. 56, an optical sensor array 254 comprising a pluralityof optical sensors 256 may be provided to read grooves 258 in the capbody 104 of the cap-bladder assembly 100. In this embodiment, theoptical sensor array 254 may sense one or both of the size of the capbody 104 and presence of the cap-bladder assembly 100 on the cylindricalbody 30 and sends signal(s) to the controller associated with the fluidinjector 12 to convey this information to the controller, and a similarsystem for size sensing of a syringe may be found in U.S. Pat. No.7,666,169 to Cowan et al. In FIG. 56, the cap-bladder assembly 100 andcylindrical body 30 are shown schematically to illustrate various sensorarrangements and details of cap-bladder assembly 100, cylindrical body30, and plunger element 50 are herein.

Referring to FIGS. 57-58, a sensor device 260 may be located external tothe cylindrical body 30 to detect the presence and position of thebladder 1140 and/or to determine the volume of fluid present in thebladder 1140, or other properties associated with the bladder 1140. Theexternal sensor device 260 may be an optical sensor device 260 that maybe used to optically determine the presence and position of the bladder1140 and/or to determine the volume of fluid present in the bladder1140. The external sensor device 260 may also be used to sense aleak/rupture of the bladder 1140 as the position of the bladder 1140changes abruptly when there is a complete rupture and not in sync withmovement of the plunger element 50. The external sensor device 260 mayalso be adapted to read volume or other indicia markings 1262 on thebladder 1140, such as a bar code. The external optical sensor device 260may alternatively be an ultrasound sensor device 260 that is used tocheck for liquid and air in the bladder 1140. As described previously,lines, grooves, or markings or other indicia 1100 may be provided in thetop or distal side 1150 of the membrane portion 1146 of the bladder 1140which provide a visual indication to attendant medical personnel of thebladder 1140 being filled with fluid and in a stretched state, and theselines, grooves, or markings 1100 may likewise be read by the externaloptical sensor device 260 as the bladder 1140 is stretched duringfilling. In case of failure of the bladder 1140, the external opticalsensor device 260 would likewise register the failure. The markings 1100may be used additionally for decorative purposes or to identify thesource or origin of the cap-bladder assembly 100, and may further be abar code.

Referring to FIGS. 59A-59B, an embodiment is shown useful for visuallydetermining when there is fluid in the filled bladder 1140. In FIGS.59A-59B, the membrane portion 1146 of the bladder 1140 is provided withfibers 264 on the on the top or distal side 1150 which float in thepresence of fluid, as shown in FIG. 59A. If no fluid is present, thefibers curl over or lie flat against the top or distal side 1150 of themembrane portion 1146 of the bladder 1140, as shown in FIG. 59B. One ormore of the sensors described previously, such as the optical sensor 204and the external optical sensor device 260 may be used as an opticaldetector to sense the presence of the fibers 264. In FIGS. 59A-59B, thecap-bladder assembly 100, cylindrical body 30, and plunger element 50are shown schematically to illustrate various sensor arrangements anddetails of the cap-bladder assembly 100, cylindrical body 30, andplunger element 50 are found in the foregoing.

Referring to FIGS. 60A-60B, a floating actuator 266 may be providedinside the cap body 104 which only allows fluid injection if fluid ispresent in the bladder 1140. In this embodiment, a check valve 268 maybe provided in the discharge conduit 110 of the cap body 104 that isnormally closed to fluid flow outward from the bladder syringe 20. Theoutlet check valve 268 permits fluid to enter the bladder syringe 20.The outlet check valve 268 is overridden by the floating actuator 266.The floating actuator 266 comes into contact with the outlet check valve268 to override the check valve when the bladder 1140 is filled withfluid, as shown in FIG. 60B. Otherwise, the outlet check valve 268remains closed and prevents the ejection of fluid, either liquid or air,from the bladder syringe 20. In FIGS. 60A-60B, the cap-bladder assembly100, cylindrical body 30, and plunger element 50 are shown schematicallyto illustrate various sensor arrangements and details of the cap-bladderassembly 100, cylindrical body 30, and plunger element 50 are found inthe foregoing.

Referring to FIG. 61, the bladder syringe 20 is illustrated with thedisposable fluid path or set 200, discussed previously, which isconnected to the threaded end connector 112 at the end of the dischargeconduit 110 of the cap body 104. The disposable fluid set 200 mayinclude tubing 201 for delivering fluid to a patient and this tubing 201may include additional fluid carrying arrangements (not shown) forplacing the bladder syringe 20 in fluid communication with one or morebottles or bags containing desired injection fluid. With respect to FIG.61, it has been observed that variations in the volume of entrapped airbetween the plunger element 50 and the bladder 1140 may causeinaccuracies in fluid delivery. When air is present between the plungerelement 50 and the bladder 1140, the initial fluid delivery lags whilethis air is compressed. After the air is compressed, the volume flowrate behaves as it would in a positive displacement syringe (e.g., atypical syringe used in power fluid injectors). To adjust for theforegoing inaccuracies, as shown in FIG. 61, the bladder syringe 20 maybe mated with two pressure transducers 270, 272, for example, byassociating the pressure transducers 270, 272 with the discharge conduit110 of the cap body 104. In particular, the bladder syringe 20 isconfigured to have the cap-bladder assembly 100 mated with two pressuretransducer sensing ports 274, 276 placed on a membrane 278 provided inthe discharge conduit 110 of the cap body 104. The pressure transducersensing ports 274, 276 accept and support the pressure transducers 270,272. During an injection, while fluid is flowing from the bladdersyringe 20 through the tubing 201, there is a pressure differencebetween the two transducers 270, 272. Using the pressure differencebetween the transducers 270, 272, the volume flow rate can becalculated. The controller of the fluid injector 12 compares thecalculated flow rate with the programmed flow rate and varies the speedof the piston element 14 as needed to achieve the programmed flow rateand volume delivery. This control method minimizes the effects of theair trapped between the bladder 1140 and plunger element 50 since thefluid injector 12 compensates for lower flows (e.g., while the air isbeing compressed) by increasing the speed of the plunger element 50interfaced with the piston element 14. The foregoing pressure sensingarrangement using two pressure transducers 270, 272 may be utilized withany syringe having a distal discharge conduit similar to dischargeconduit 110 of the cap body 104 and is not limited to use with bladdersyringe 20. Using the arrangement in FIG. 61, the rate and time requiredto reach a desired pressure can be tracked as can pressure differentialover time to determine flow rate.

In FIG. 61, the membrane 278 could also be adapted to provide a knownrestriction in the outlet path of the bladder syringe 20, such that aknown pressure would be required to overcome the restriction. If thefluid injector 12 applied a Fill/Prime sequence to fill the bladdersyringe 20 with fluid, the pressure sensing arrangement shown in FIG. 61may be used to measure the pressure in the discharge conduit 110 of thecap body 104, and the controller associated with the fluid injector 12can track the rate and time it takes to achieve a desired pressure. Ifthe bladder syringe 20 is filled with a liquid (e.g., an incompressiblefluid), the rate and time needed to arrive at the desired pressureshould be short and close to instantaneous. If air (e.g., a compressiblefluid) is present, there will be a gradual ramp-up in pressure. Thecontroller associated with the fluid injector 12 can track rate and timerequired to reach the desired pressure and can interpolate if there isair in the bladder syringe 20.

Referring to FIGS. 62A-62B, the interior wall 36 of the cylindrical body30 and/or the interior cavity 106 of the cap body 104 of the cap 102 inthe cap-bladder assembly 100 may be frosted as represented by thealternating shaded lines or regions 298 in FIG. 62A which, when exposedto liquid, becomes clear as represented in FIG. 62B. The frosting may befine surface texture on the fluid side of the cylindrical body 30 and/orcap body 104. This fine surface texture would be such that it affectslight transmission by diffusing light in the presence of air and wouldnot affect light transmission in the presence of a liquid as the liquidfills-in the fine surface texture with liquid and becomes moretransparent. The frosted fine surface texturing may also be provided onthe distal portion 52 of the plunger element 50 as well. The frostedfine surface texturing may also be provided on any internal surface of asyringe and/or plunger in accordance with this disclosure such as asyringe used in the fluid injector 12 shown in FIG. 7 describedpreviously, or any fluid conveying device such as a pump body, tubingset, or valve body to indicate when liquid is present on the texturedsurface on the body.

Referring to FIGS. 63A-63B, a sensor array 300 may be provided in thebore of the cylindrical body 30 and on the interior wall 36 thereof inthis embodiment of the bladder syringe 20. The sensor array 300 isdesirably embedded into the interior wall 36 of the cylindrical body 30.The sensor array 300 may be a capacitive sensor array 300 fordetermining the position of the bladder 1140 within the cylindrical body30 during filling and, hence, for determining volume of fluid present inthe bladder 1140. The sensor array 300 may further be adapted for linearresistive and/or impedance measurement of the position of the bladder1140 within the cylindrical body 30 during filling and, hence, fordetermining volume of fluid present in the bladder 1140. Moreover, thesensor array 300 may further be adapted for capacitive orradio-frequency (RF) impedance measurement of the position of thebladder 1140 within the cylindrical body 30 during filling and, hence,for determining volume of fluid present in the bladder 1140.Furthermore, the sensor array 300 may further be adapted for ultrasonicmeasurement of the position of the bladder 1140 within the cylindricalbody 30 during filling and, hence, for determining volume of fluidpresent in the bladder 1140. The cap 102 of the cap-bladder assembly 100is omitted in FIGS. 63A-63B as are specific details of theconnection/interaction of the cap-bladder assembly 100 with thecylindrical body 30 for simplicity. The positional and/or volumeinformation regarding the bladder 1140 may be communicated by the sensorarray 300 to the controller of the fluid injector 12 for controllingoperation of the fluid injector 12. As another alternative, the lines,grooves, or markings 1100 on the bladder 1140, as shown in FIG. 12Adiscussed previously, or indicia markings 262 discussed previously inconnection with FIG. 58 may comprise one part of a radio-frequency (RF)or capacitive circuit, and the second part of this circuit may be partof the sensor array 300, and a sensed change of impedence or capacitancein this circuit is indicative of leakage or failure of the bladder 1140.As a further alternative, the lines, grooves, or markings 1100 on thebladder 1140, as shown in FIG. 12A discussed previously, or indiciamarkings 262 discussed previously in connection with FIG. 58 may beconductive and, as the bladder 1140 expands during filling, reach thesensor array 300, and the sensor array 300 detects resistance changesalong the bladder 1140; a sensed rapid change in this resistance isindicative of leakage or failure of the bladder 1140.

Referring to FIG. 64, fluid detection for fluid in the cap 102 of thecap-bladder assembly 100 may also be provided by devices associated withthe cap body 104. In FIG. 64, two (2) electrical leads 302, 304 may beprovided in the cap body 104 to read the electrical resistance betweenthe leads. If air alone is present, the resistance is infinite and inthe presence of a conductive liquid the, resistance drops. This changein resistance is registered by the controller of the fluid injector 12and indicates that liquid is present in the interior cavity of the capbody 104. One or both of the electrical leads 302, 304 may alternativelybe an electrode and a second electrode may be formed by conductivematerial placed on the interior wall 36 of the cylindrical body 30and/or on the plunger element 50 and an amp meter is connected to theelectrodes operating at a low, patient-safe current. In the case of aleak or failure of the bladder 1140, a current larger than a thresholdcurrent indicates a leak or rupture of the bladder 1140.

Referring to FIGS. 65A-65C, another method of fluid detection for fluidin the cap 102 of the cap-bladder assembly 100 comprises opticaldetection using a light pipe 306 that detects light reflectance changesin the presence of fluid in the cap body 104 of the cap 102. The lightpipe 306 conducts light from an external light source, such as locatedin the housing 18 of the fluid injector 12 and conducts the light to thecap body 104 where the light enters into the cap body 104 at such anangle that the light would be trapped in the light pipe 306 andreflected back to the fluid injector 12 in the presence of air. In thepresence of air, as shown in FIG. 65B, the difference between the indexof refraction of air and the plastic cap body 104 and the exit anglewould be so high that the light would be internally reflected inside thelight pipe 306. When liquid is present, as shown in FIG. 65C, the indexof refraction is closer to that of the plastic cap body 104 and thelight is able to escape, and there is no internal reflection returningto the fluid injector 12. In FIGS. 65A-65B, the cap-bladder assembly100, cylindrical body 30, and plunger element 50 are shown schematicallyto illustrate various sensor arrangements and details of the cap-bladderassembly 100, cylindrical body 30, and plunger element 50 are foundherein.

Referring to FIG. 66, another embodiment of the bladder syringe 20 isshown that incorporates a plunger element 50 in which a hollow cavity orwell 308 is provided between the distal portion 52 and the proximalportion 54 of the plunger element 50. The plunger well 308 is in fluidcommunication with the bore of the cylindrical body 30 by a plurality ofapertures 310 in the distal portion 52 of the plunger element 50. In theevent the bladder 1140 leaks or ruptures, fluid enters the plunger well308 via the apertures 310 and, for example, contacts a fluid sensor 312in the proximal portion 54 of the plunger element 50. The fluid sensor312 may, for example, register fluid upon the completion of connection.Such an electrical connection may result, for example, by providing theconductive elements 218 described previously in the plunger well 308.Fluid detection in the plunger well 308 using the fluid sensor 312 maybe accomplished by any of the foregoing described techniques, such asoptical, ultrasonic, electrical connectivity completion, fluid sensor,etc. If desired, the proximal portion 54 of the plunger element 50 maybe adapted for limited movement relative to the distal portion 52, andthis movement creates the plunger well 308 and, further, causes a vacuumin the plunger well 308 that pulls in fluid into the plunger well 308.The plunger well 308 may contain an absorbent material 314 that issuitable to disperse fluid and allow one or more sensors in the plungerwell 308 to register the presence of fluid and a leak or rupture of thebladder 1140.

In FIG. 67, another embodiment of the bladder syringe 20 is shown thatincorporates a flapper or duckbill valve 316 that is attached to the cap102 of the cap-bladder assembly 100. The flapper or duckbill valve 316is attached by one circumferential connection 318 to the cap body 104 inthe interior cavity 106 thereof and is adapted to mechanically releasefrom the cap body 104 under the stress induced when the bladder 1140ruptures. As illustrated in FIG. 67, the flapper or duckbill valve 316is further connected by a second circumferential connection 320 to thebladder 1140 so that when the bladder 1140 ruptures, the flapper orduckbill valve 316 is released and halts any fluid flow from the bladdersyringe 20. The controller of the fluid injector 12 automaticallyexperiences a sharp rise in back pressure and ceases operation. Detailsof the cap-bladder assembly 100, cylindrical body 30, and plungerelement 50 are omitted in FIG. 67 and the components are illustratedschematically only.

In the numerous embodiments of the bladder 1140 described previously,the bladder 1140 is typically shown as a singular membrane. However, asshown in FIG. 68, the bladder 1140 may comprise a second safety liner1141 either molded with the bladder 1140 or otherwise incorporated intothe cap-bladder assembly 100 as a safety liner in case of failure of thebladder 1140. The safety liner 1141 may be made of latex and likematerials. Moreover, in the numerous embodiments of the bladder 1140described previously, the bladder 1140 is typically shown as part of thecap-bladder assembly 100. However, as shown in FIGS. 69A-69B, thebladder 1140 may also be provided at other locations in the cylindricalbody 30, such as covering the proximal end 34 of the cylindrical body30. The plunger element 50 is operable as a conventional displacementplunger like those used in conventional syringes and air in thecylindrical body 30 distal or forward of the bladder 1140 is exhaustedtherefrom via the discharge conduit 110 by forward or distal movement ofthe plunger element 50. Reverse movement of the plunger element 50 drawsfluid into the syringe-type cylindrical body 30 in this embodiment. Thecap body 104 is integral with the cylindrical body 30 in thisembodiment.

Referring to FIGS. 70A-70B, an embodiment of the cap 102 of thecap-bladder assembly 100 is shown having two (2) different embodimentsof high-crack pressure bi-directional check valves 322, 324 disposed tocontrol fluid into and from the discharge conduit 110 and which provideresistance to facilitate purging of air from behind the bladder 1140 asthe plunger element 50 moves forward without requiring a separate plugor blocking of the discharge conduit 110. The check valves 322, 324enable air to be purged from the cap body 104 and reduce or eliminatethe possibility of pulling unwanted fluid (e.g., blood) into the capbody 104 and, further, reduce the possibility of unintended discharge offluid (e.g., a gravity flow condition, etc.) from the cap body 104. InFIG. 70A, the check valve 322 is a collapsible column that collapses atpredetermined or preset pressure to allow fluid to pass, and in FIG. 70Bthe check valve 324 is conventional slit-type check valve. A removabledust cap 326 is also shown in these figures which is suitable for use inany of the embodiments of cap 102 in this disclosure.

Referring next to FIGS. 71A-71C, another bladder syringe 20 is shownthat incorporates an alternative method for securing the cap-bladderassembly 100 to the cylindrical body 30. In this embodiment, the distalend 32 of the cylindrical body 30 comprises an enlarged end flange 400with a snap closure element 402 that extends upward or distally from theend flange 400. The snap closure element 402 has a barbed end 403.Additionally, the end flange 400 has a distal rim 404 with inner andouter circumferential walls 406, 408 that define an annular recess 410therebetween. The inner circumferential wall 406 is slightly shorter inheight than the outer circumferential wall 408. A cap or cover 412 isconnected by a hinge 414 to the end flange 400 on the opposite side fromthe snap closure element 402. The cap or cover 412 has an overall shapeto accept the cap-bladder assembly 100 therein. The cap or cover 412comprises an interior cavity 416 to receive the cap-bladder assembly 100and has a tubular end portion 418 that receives the discharge conduit110 on the cap body 104 of the cap 102. The cap or cover 412 furthercomprises a proximal rim 420 that is sized to fit over the distal rim404 on the end flange 400 and, in particular, over and around the outercircumferential wall 408 of the distal rim 404. The proximal rim 420comprises an attachment tab 422 for engagement by the snap closureelement 402 to secure the cap or cover 412 to the end flange 400 duringuse of the bladder syringe 20 in this embodiment.

In this embodiment, the cap-bladder assembly 100 is modified to operatewith the hinged cover 412 and distal rim 404 on the end flange 400. Thecap-bladder assembly 100 comprises a cap 102 wherein the cap body 104and bladder 1140 are, desirably, co-injection molded together, in asimilar manner to the embodiment shown and as described previously inconnection with FIG. 47A wherein the bladder 1140 was described as beingco-injection molded with the inner liner 194. The retainer ring 140 maybe eliminated in this embodiment. Further, the cap body 104 is formedwithout the cylindrical portion 114 described previously. Accordingly,as shown in detail in FIG. 71C, an exterior circumferential rim 424 ofthe cap body 104 is molded to an exterior circumferential rim 1264 ofthe bladder 1140. Alternatively, the circumferential rims 424, 1264 maybe secured by other means such as ultrasonic welding, adhesive, and likejoining methods. The exterior rim 1264 on the bladder 1140 comprises adepending rib 1266 adapted to be received in the annular recess 410between the inner and outer circumferential walls 406, 408 of the distalrim 404. The engagement of the barbed end 403 on the snap closureelement 402 with the attachment tab 422 on the proximal rim 420 of thecover 412 further secures the depending rib 1266 in the annular recess410 in a fluid-tight connection to enable a vacuum to be drawn in thecylindrical body 30 by the plunger element 50, which is not shown inFIGS. 71A-71C and details of various embodiments the plunger element 50may be found in the foregoing.

To attach the cap-bladder assembly 100 to the cylindrical body 30 inthis embodiment, an attendant medical practitioner typically removes thecap-bladder assembly 100 from its packaging and places the cap-bladderassembly 100 in association with the end flange 400 on the cylindricalbody 30 so that the depending rib 1266 on the circumferential rim 1264of the bladder 1140 is received in the annular recess 410 between theinner and outer circumferential walls 406, 408 of the distal rim 404 onthe end flange 400. Next, the user pivots the hinged cover 412 so thatthe proximal rim 420 fits over the distal rim 404 on the end flange 400and, in particular, over and around the outer circumferential wall 408of the distal rim 404. As the hinged cover 412 is pivoted toward the endflange 400, the proximal rim 420 engages the barbed end 403 on the snapclosure element 402 and displaces the snap closure element 402 radiallyoutward to enable the proximal rim 420 to seat around the outercircumferential wall 408 of the distal rim 404. The attachment tab 422on the proximal rim 420 is generally aligned with the barbed end 403 sothat as the proximal rim 420 fits over the distal rim 404 on the endflange 400 the barbed end 403 snaps into engagement onto the attachmenttab 422 and secures the hinged cover 412 to the end flange 400 andprovides a generally or substantially fluid-tight seal between thedepending rib 428 in the annular recess 410.

Referring next to FIGS. 72A-72B, another embodiment of the bladdersyringe 20 is shown that incorporates the cylindrical body 30 into theinterior of the housing 18 of the fluid injector 12 and the cap-bladderassembly 100 is secured directly to the fluid injector housing 18. InFIGS. 72A-72B, the cylindrical body 30 is disposed in the interior ofthe fluid injector housing 18. A distal end 430 of the fluid injectorhousing 18 supports a clamping assembly 432 comprising a fixed arm 434and a pivotal swing arm 436 each defining an arcuate recess 438 therein.The clamping assembly 432 may be automatically operable by thecontroller associated with the fluid injector 12. As in the embodimentof the cap-bladder assembly 100 discussed above in connection with FIGS.71A-71C, the cap body 104 in this embodiment is formed without thecylindrical portion 114 described previously. In present embodiment, theexterior circumferential rim 424 of the cap body 104 is molded orotherwise attached to the exterior circumferential rim 1264 (not shownin FIGS. 72A-72B) of the bladder 1140. Additionally, in the presentembodiment, the exterior circumferential rim 424 of the cap body 104 isenlarged radially as compared to the embodiment shown in FIGS. 71A-71Cto fit within the mating arcuate recesses 438 in the fixed arm and swingarm 434, 436 of the clamping assembly 432. Details of the connectionbetween the cap-bladder assembly 100 and cylindrical body 30 are omittedin FIGS. 72A-72B but may be similar to that described in the foregoingin connection with FIGS. 71A-71C. As illustrated, a user simply matesthe cap-bladder assembly 100 to the cylindrical body 30 disposed in thefluid injector housing 18 while further placing the exteriorcircumferential rim 424 on the cap body 104 into the arcuate recess 438in the fixed arm 434 and then pivots the swing arm 436 so that thearcuate recess 438 therein likewise engages the exterior circumferentialrim 424 on the cap body 104. A lock or other securing connection (notshown) is provided between the fixed arm 434 and swing arm 436 to securethe circumferential rim 424 in the mating arcuate recesses 438 in thefixed arm 434 and swing arm 436.

Referring to FIGS. 73A-73E, another bladder syringe 20 is shown thatincorporates another alternative method for securing the cap-bladderassembly 100 to the cylindrical body 30. In this embodiment, the distalend 32 of the cylindrical body 30 comprises an enlarged end flange orrim 440 with inner and outer circumferential walls 446, 448 that definean annular recess 450 therebetween. The inner circumferential wall 446is slightly larger in height and tapered as compared to the outercircumferential wall 448. Additionally, two (2) axially spaced radialflanges 452, 454 are provided on the cylindrical body 30 axially belowthe end flange or rim 440. A pair of axial walls 456 extends between theradial flanges 452, 454 which act as rotation stops as described herein.The proximal end 34 of the cylindrical body 30 is formed with acircumferential flange 38 positioned to engage the front end of thehousing 18 of the fluid injector 12 to properly seat the cylindricalbody 30 relative to the fluid injector 12 as in previous embodiments,and a suitable connecting arrangement for mounting the proximal end 34of the cylindrical body 30 to a power fluid injector may be found inU.S. Pat. No. 7,450,856 to Hitchins et al., incorporated herein byreference. In FIGS. 73A-73E, a flex-leg connecting assembly 480 is usedto secure the cap-bladder assembly 100 to the distal end 32 of thecylindrical body 30.

In the present embodiment, the cap-bladder assembly 100 is modified tooperate with the flex-leg connecting assembly 480. The cap-bladderassembly 100 comprises a cap 102 wherein the cap body 104 and bladder1140 are, desirably, co-injection molded together, and the retainer ring140 may again be eliminated in this embodiment. Further, the cap body104 is formed without the cylindrical portion 114 described previously.The cap-bladder assembly 100 is substantially similar to the embodimentshown in FIG. 47C discussed previously. In that embodiment, the cap 102has a cap body 104 with a co-injection molded bladder 1140, with themembrane portion 1146 having central well portion 1268. In theembodiment of FIGS. 73D-73E, the central well portion 1268 is surroundedby a thickened circumferentially region 1270. As shown in FIGS. 73D-73E,the distal side 1150 of the membrane portion 1146 generally conforms tothe internal shape of the interior cavity 106 of the cap body 104 andthe opposing proximal side 1152, including the central well portion 1268and surrounding thickened region 1270, defines a profile or shape thatmatches the profile of the plunger element 50 (see FIG. 47C), which isomitted in FIGS. 73D-73E. Additionally, in FIGS. 73D-73E, the bladder1140 and the cap body 104 have outer circumferential rims or flanges1272, 1278, respectively, that are joined together in the co-injectionmolding process, but these outer circumferential rims or flanges 1272,1278 lack the mutually engaging ribs 1274, 1280 and 1276, 1282 describedpreviously in connection with FIG. 47C. However, these features may beprovided if so desired. As an alternative, the outer circumferentialrims or flanges 1272, 1278 may be joined by other joining methods suchas ultrasonic welding, laser welding, adhesive joining, and like joiningtechniques. Accordingly, as shown in FIGS. 73D-73E, an exteriorcircumferential rim 1278 of the cap body 104 is joined to an exteriorcircumferential rim 1272 of the bladder 1140 and a composite end flangeor rim 1290 defined by this molded joint is adapted to be received inthe annular recess 450 defined between the inner and outercircumferential walls 446, 448 of the enlarged end flange or rim 440 onthe distal end 32 of the cylindrical body 30.

With continued reference to FIGS. 73A-73E, the flex-leg connectingassembly 480 is comprised by a composite flex legs inner sleeve 482disposed within a rotating outer sleeve 500. The composite flex legsinner sleeve 482 is a split-ring component formed by two (2) opposingsplit-ring halves 484 which each have a plurality of distally-extendingcontact flex legs 486. The interior of each of the split-ring halves 484has a pair of radially-inward extending flanges 488, 490 adapted to bereceived and sandwiched between the two (2) radially-outward extendingflanges 452, 454 on the cylindrical body 30. The exterior of each of thesplit-ring halves 484 comprises a series of external threads 492. Theopposing free ends of the split-ring halves 484 may be adapted forfrictional interengagement, if desired, to secure the two (2) split-ringhalves 484 together, or a locking connection (not shown) may be providedto secure the free ends. Desirably, the pair of axial walls 456 thatextends between the radial flanges 452, 454 on the cylindrical body 30engage a recess or groove (not shown) in the interior of the opposingsplit-ring half 484 and this engagement acts as rotation stops so as toprevent rotation of the composite flex legs inner sleeve 482 onceassembled by joining the two (2) split-ring halves 484 together aroundthe cylindrical body 30.

The outer sleeve 500 comprises a curved distal end or portion 502 thatdefines an opening 504 sized to receive the cap-bladder assembly 100therethrough, and is adapted to fit over the composite flex legs innersleeve 482. The outer sleeve 500 has a sidewall 506 extending from thedistal end or portion 502 that is of a sufficient axial length toentirely enclose the composite flex legs inner sleeve 482. The interiorside of the sidewall 506 comprises mating threads 508 to engage theexterior threads 492 on the exterior of each of the split-ring halves484. The outer sleeve 500 is connected to the composite flex legs innersleeve 482 by threaded engagement between the mating threads 492, 508.When the outer sleeve 500 is rotated relative to the inner sleeve 482,the outer sleeve 500 is either drawn axially downward along the innersleeve 482 or moves axially upward along the inner sleeve 482. In anopen position of the flex-leg connecting assembly 480, as shown in FIG.73D, the outer sleeve 500 is in a position relative to the inner sleeve482 to radially position the contact flex legs 486 at a radial positionthat allows the cap-bladder assembly 100 to be inserted through thedistal opening 504 and be connected to the cylindrical body 30. In thisconnection or engagement, the composite end flange or rim 1290 definedby the exterior circumferential rim 1278 of the cap body 104 and theexterior circumferential rim 1272 of the bladder 1140 is received in theannular recess 450 defined between the inner and outer circumferentialwalls 446, 448 of the enlarged end flange or rim 440 on the distal end32 of the cylindrical body 30. To secure this engagement, the outersleeve is rotated, for example clockwise, relative to the inner sleeve482 to arrive at the closed position, shown in FIG. 73E, wherein theflex legs 486 are displaced radially inward to engage the composite endflange or rim 1290 which secures the cap-bladder assembly 100 in place.As shown in FIG. 73E, the clockwise rotational movement of the outersleeve 500 causes the mating threads 492, 508 to draw the outer sleeve500 axially downward along the inner sleeve 482, and this motion causesthe internally curved distal end or portion 502 of the outer sleeve 500to contact an externally curved distal end 510 on each of the flex legs486 and deflects the flex legs 486 radially inward to engage thecomposite end flange or rim 1290 on the cap-bladder assembly 100.Reverse rotational movement of the outer sleeve 500 causes reversemovement and releases the flex legs 486 from the locking position shownin FIG. 73E as the outer sleeve 500 moves axially upward along the innersleeve 482. Once the flex legs 486 disengage from the composite endflange or rim 1290 on the cap-bladder assembly 100, the cap-bladderassembly 100 may be removed for disposal. The flex legs 486 areresiliently flexible to move to the position shown in FIG. 73D when notacted upon by the internally curved distal end 502 of the outer sleeve500. The flex-leg connecting assembly 480 has numerous advantages. Forexample, the loading of the cap-bladder assembly 100 is non-orientationspecific and does not require rotation during assembly so that thebladder 1140 is not subject to torque or twisting motion. Additionally,all components of the flex-leg connecting assembly 480 may bepermanently connected to the cylindrical body 30 during manufacturingand there will be no loose parts for the end user to assemble.

Referring next to FIGS. 74A-74B, an adapter assembly 570 is shown forconnecting the plunger element 50, such as the embodiment shown in FIG.10A, to a conventional or known plunger 550 adapted for connection to apiston element of a power fluid injector, such as the piston element 14of the fluid injector 12 discussed previously. The depicted embodimentof the plunger 550 may be a plunger manufactured by Imaxeon and providedin a 200 ml syringe used in a power fluid injector sold under thetrademark Salient® and shown in International Publication No. WO2009/036496, incorporated herein by reference. The plunger 550 comprisesa conical distal end or portion 552, cylindrical proximal end or portion554, and an intervening annular recess or groove 556 between theportions 552, 554. The plunger element 50 in this embodiment has aunitary body component with a conical distal portion 52 and acylindrical proximal portion 54, and a seal ring 88 is disposed in anannular recess or groove 558 defined in the proximal portion 54.However, a two-piece plunger element 50 split at annular recess orgroove 558 may also be used in this embodiment. In the embodiment of theplunger element 50 depicted in FIG. 10A, the conical distal portion 52and the cylindrical proximal portion 54 are separate components that arejoined together. In the embodiment of the plunger element 50 shown inFIGS. 74A-74B, the distal portion 52 defines an annular recess or groove560 proximal of the annular recess or groove 558 that supports the sealring 88.

The adapter assembly 570 is comprised of two (2) split-ring elements orhalves 572 which each have a pair of radially-inward extending flanges574, 576 adapted to be received, respectively, in the annular recess orgroove 560 in the proximal portion 54 of the plunger element 50 and theannular recess or groove 556 in the plunger 550, thereby connecting theplunger element 50 with the plunger 550. The opposing free ends of thesplit-ring halves 572 may be adapted for frictional interengagement tosecure the two (2) split-ring halves 572 together, or a lockingconnection or mechanism (not shown) may be provided to secure the freeends together. As shown in FIG. 74B, the interior wall 36 of thecylindrical body 30 radially supports the two (2) split-ring halves 572in an assembled configuration. As this figure shows, the adapterassembly 570 may be used to convert a conventional or known plunger 550for use as part of the bladder syringe 20. In the bladder syringe 20 ofFIG. 74B, the cap-bladder assembly 100 is modified as is the distal end32 of the cylindrical body 30. The cap body 104 of the cap 102 comprisesan enlarged circumferential rim 580 that cooperates with a correspondingcircumferential rim 582 on the distal end 32 of the cylindrical body 30.A plurality of apertures 584 may be formed by the connection of thecircumferential rims 580, 582 that accept connecting mechanicalfasteners and like connecting elements (not shown) to secure thesecomponents together. The bladder 1140 of the cap-bladder assembly 100 inthis embodiment is generally similar to that discussed previously inconnection with FIGS. 12A-12B. The air-venting and vacuum-generatingfeatures of the plunger element 50 are generally similar to those shownand discussed in connection with FIG. 10A. The connection of the capbody 104 onto the cylindrical body 30 in this embodiment may be similarto that shown in FIGS. 73A-73E discussed previously.

Referring now to FIGS. 75-81, as noted previously, it is desirable toprovide a sterile packaging arrangement for the cap-bladder assembly 100used in the bladder syringe 20. In FIG. 75, the cap-bladder assembly 100may be prepackaged with two removable shipping caps 588, 590 forcovering, respectively, the end connector 112 on the discharge conduit110 of the cap body 104 and the second covering the opposing open end ofthe cap body 104. The depicted and non-limiting embodiment of thebladder 1140 is similar to the embodiment shown in FIGS. 24A-24B inwhich the membrane portion 1146 is shaped like a flat trampoline with athinner section 1190 in the center and a thicker outer section 1192tapering from the thinner center section 1190.

In FIG. 76, a packaging container 600 is shown with a cup-shaped body602 that fits over the cap-bladder assembly 100 and comprises opposinginternal stabilizers 604, 606 that engage, respectively, the tworemovable shipping caps 588, 590. The open end of the cup-shaped body602 comprises a protective seal 608, typically a sterilized seal, thatis peeled away to remove the cap-bladder assembly 100. The fluid pathset 200 may also be sealed in the packaging container 600.

In FIG. 77, a packaging container 610 is shown with a multi-well body612 for receiving several cap-bladder assemblies 100. The multi-wellbody 612 enables the packaging container 610 to be nested or stackedwith another packaging container 610 in an opposed or mirror-imagearrangement. The open end of the multi-well body 612 comprises aprotective seal 614, typically a sterilized seal, that is peeled away toremove the cap-bladder assemblies 100.

In FIG. 78, a packaging container 620 is shown with a single-well body622 for receiving several cap-bladder assemblies 100 in end-to-endrelationship, wherein the discharge conduits 110 on the respectivecap-bladder assemblies 100 face one another. The open end of thesingle-well body 622 comprises a protective seal 624, typically asterilized seal, that is peeled away to remove the cap-bladderassemblies 100. FIG. 79 illustrates a variation of the packagingcontainer 620, wherein the cap-bladder assemblies 100 are in end-to-endrelationship, but the open ends of the cap body 104, optionally closedby shipping caps 590 discussed previously, in the respective cap-bladderassemblies 100 face one another.

In FIG. 80, the cap-bladder assemblies 100 are placed on a longbandolier protective strip 626 which serves to protect the open ends ofthe cap body 104. As a cap-bladder assembly 100 is required, it couldjust be pulled off the bandolier protective strip 626 that may furtherbe adapted to protect the sterility of the interior of the cap body 104for each cap-bladder assembly 100. If desired, the shipping cap 590,discussed previously, enclosing the open end of the cap body 104 in eachcap-bladder assembly 100 may be affixed to the bandolier strip 626 andthen remain with the strip 626 while the remainder of the cap-bladderassembly 100 is removed.

In FIGS. 81A-81B, a packaging container 630 is shown with a cup-shapedbody 632 that forms an upper portion of the packaging container 630. Thecup-shaped body 632 is further integrally formed with the cap body 104of the cap 102 of the cap-bladder assembly 100. The cap body 104comprises a short radial flange or rim 634 that connects to thecylindrical portion 114 of the cap body 104. The cylindrical portion 114forms a lower part or portion of the packaging container 630. Thus, thecap body 104 and the cylindrical portion 114 thereof form part of thepackaging container 630. The open top end of the cup-shaped body 632 issealed by a protective seal 638, typically a sterilized seal, that ispeeled away to remove the cap-bladder assembly 100. Likewise, the openend of the cap body 104 defined by the cylindrical portion 114 is sealedby a protective seal 640, typically a sterilized seal, that is peeledaway to access the bladder 1140 in the cap body 104, which is not shownin FIG. 81B for simplicity. Moreover, a score line 642 or other methodfor detaching the cap body 104 from the cup-shaped body 632 is providedbetween these components. A plurality of the packaging containers 630may be stored in end-to-end relationship in a tubular shipping containerwhich may have a suitable end or side opening to permit individualcontainers 630 to be removed one at a time.

Referring next to FIGS. 82-83 in combination with FIGS. 73A-73E, thecap-bladder assembly 100, in the exemplary embodiment shown in FIGS.73A-73E, is again generally depicted. In this exemplary and non-limitingembodiment, the bladder 1140 and the cap body 104 has outercircumferential rims or flanges 1272, 1278, respectively, that arejoined together in the co-injection molding process, but these outercircumferential rims or flanges 1272, 1278 lack the mutually engagingribs 1274, 1280 and 1276, 1282 described previously in connection withFIG. 47C. However, these features may be provided if so desired. As analternative, the outer circumferential rims or flanges 1272, 1278 may bejoined by other joining methods such as ultrasonic welding, laserwelding, adhesive joining, and like joining techniques. Accordingly, inthe embodiment shown in FIGS. 73A-73E, an exterior circumferential rim1278 of the cap body 104 is joined to an exterior circumferential rim1272 of the bladder 1140 to form a composite end flange or rim 1290. InFIGS. 82-83, the end flange or rim 1290 comprises a plurality ofradially-outward extending tabs or tab members 1300 that are adapted tobe received in corresponding slots 1302, such as bayonet-slots 1302defined in an end rim 1304 and the interior wall 36 of the cylindricalbody 30 at the distal end 32 of the cylindrical body 30. In use, as thetab members 1300 engage the receiving slots 1302 and the cap body 104 isrotated in a clockwise or counterclockwise direction depending on theorientation of the slots 1302, the cap-bladder assembly 100 is securedto the distal end 32 of the cylindrical body 30. Suitable seals may beprovided in the distal end 32 of the cylindrical body 30 so that agenerally fluid-tight seal may be established between the end flange orrim 1290 and the interior wall 36 of the cylindrical body 30. Suitableseals may comprise a recessed lip or rim (not shown) in the distal end32 of the cylindrical body 30 having a sealing surface to form agenerally fluid-tight seal with the end flange or rim 1290, or asuitable O-ring arrangement may be provided on the end flange or rim1290 to seat against the interior wall 36 of the cylindrical body 30.The foregoing sealing arrangements are exemplary and non-limiting.

Referring to FIG. 84, as described previously in connection with FIGS.73A-73E, a flex-leg connecting assembly 480 may be used to secure thecap-bladder assembly 100 to the distal end 32 of the cylindrical body30. As FIG. 84 illustrates, the flex-leg connecting assembly 480 may beassociated with the distal end 430 of the fluid injector housing 18. Inthis embodiment, the cylindrical body 30 (not shown in FIG. 84) may besupported or hidden within the fluid injector housing 18 and theflex-leg connecting assembly 480 may be mounted to the distal end 32 ofthe cylindrical body 30 according to the concepts and features describedpreviously in connection with FIGS. 73A-73E. FIG. 84 is generallyillustrative of the concept of locating the cylindrical body 30 withinthe fluid injector housing 18 and locating only the connecting mechanism(e.g., the flex-leg connecting assembly 480 in the present embodiment)at the front end or distal end 430 of the fluid injector housing 18 formounting the cap-bladder assembly 100. Thus, only the cap-bladderassembly 100 and the flex-leg connecting assembly 480 are visible to apatient. As a further alternative, the arrangement for securing thecap-bladder assembly 100 to the cylindrical body 30 shown in FIGS.71A-71C may also be associated with the front end or distal end 430 ofthe fluid injector housing 18 for mounting the cap-bladder assembly 100.Thus, only the cap-bladder assembly 100 and the mounting assembly shownin FIGS. 71A-71C are visible to a patient and the cylindrical body 30 isdisposed within the interior of the fluid injector housing 18.

Referring next to FIGS. 85-87, another method and structural arrangementfor securing the cap-bladder assembly 100 to the distal end 32 of thecylindrical body 30 is shown. In this embodiment, the cap-bladderassembly 100 may have the configuration of the cap-bladder assemblyshown in FIG. 82 with the composite end flange or rim 1290 describedpreviously. The end flange or rim 1290 has a depending tapered rim 1320adapted to pass through an opening 1322 defined by the distal end 32 ofthe cylindrical body 30. The tapered rim 1320 is spaced axially below anoptional front flange or rim 1324 on the cap body 104 of the cap 102 andwhich has an outer diameter larger than the front opening 1322 so thatthe front flange or rim 1324 will seat against an end rim or face 1326of the cylindrical body 30 surrounding the opening 1322. The frontflange or rim 1324 is provided as drip flange and is optional. Thedistal end 32 of the cylindrical body 30 is formed with internalcircumferential groove or recess 1328 in which a flex ring 1330 isdisposed. An internal seat 1331 is formed to extend radially-inward fromthe interior wall 36 of the cylindrical body 30 to provide an axial stopfor the tapered rim 1320. The flex ring 1330 defines a tapered surface1332 opposing the tapered rim 1320 and is used to secure the tapered rim1320 within the front opening 1322 in the distal end 32 of thecylindrical body 30, as shown in FIG. 87. The front flange or rim 1324on the cap body 104 seats into engagement against the end rim or face1326 of the cylindrical body 30 surrounding the opening 1322 as the flexring 1330 secures the tapered rim 1320 within the front opening 1322. Asuitable sealing element may be provided within the internalcircumferential groove or recess 1328 in which a flex ring 1330 isdisposed to provide a generally fluid-tight engagement between thecap-bladder assembly 100 and the cylindrical body 30. Details of theflex ring 1330 and operation thereof for securing the cap-bladderassembly 100 and the cylindrical body 30 may be found in U.S. Pat. No.7,419,478 to Reilly et al. and assigned to Medrad, Inc., additionallyincorporated herein by reference. In this embodiment, the cylindricalbody 30 may be disposed within the interior of the fluid injectorhousing 18 foregoing flex ring 1330 arrangement may be provided in thefront opening(s) in the cylindrical body 30 disposed in the fluidinjector housing 18 so that the cap-bladder assembly 100 as modifiedwith the depending tapered rim 1320 may be inserted into the front“flex-ring” openings 1322 in the cylindrical body 30 disposed in thefluid injector housing 18.

Referring to FIG. 88, a modification to the flex-leg connecting assembly480 described previously in connection with FIGS. 73A-73E is shown. Asdescribed previously, the flex-leg connecting assembly 480 is used tomount the cap-bladder assembly 100 to the distal end 32 of thecylindrical body 30. In the present embodiment, a rotationally-mountedactuating collar 1340 is provided around the split-ring halves 484 andmay be mounted radially-outward from the pair of radially-inwardextending flanges 488, 490 which are received between the two (2)radially-outward extending flanges 452, 454 on the cylindrical body 30.The actuating collar 1340 replaces the rotating outer sleeve 500 in thisembodiment. The cap-bladder assembly 100 may have the configuration ofthe cap-bladder assembly shown in FIG. 82 with the composite end flangeor rim 1290 described previously and also illustrated in FIGS. 73A-73E.The actuating collar 1340 is rotationally-mounted on the split-ringhalves 484 to act upon the flex legs 486. The actuating collar 1340 inone rotational position, which may be termed a normally closed position,permits the end flange or rim 1290 to be inserted axially intoengagement with the flex legs 486. The flex legs 486 in the normallyclosed position of the actuating collar 1340 are unflexed. In thisstate, the cap-bladder assembly 100 may be inserted axially into theflex legs 486 and the flex legs 486 are deflectable radially-outward tosnap into engagement with the end flange or rim 1290. The interior ofthe actuating collar 1340 may be formed with an internal element ormechanism (not shown), such as a cam mechanism which, when the actuatingcollar 1340 is rotated in an unlocking direction, acts upon each of theflex legs 486 and deflects the flex legs 486 radially outward todisengage the composite end flange or rim 1290 on the cap-bladderassembly 100 to release the same from the distal end 32 of thecylindrical body 30. An O-ring may be disposed between the end flange1290 and the distal end 32 of the cylindrical body 30 to form agenerally fluid-tight condition between the end flange 1290 and thedistal end 32 of the cylindrical body 30. If desired, the foregoingflex-leg connecting assembly 480 and the actuating collar 1340 mayalternatively be may be provided on the cap-bladder assembly 100 ratherthan on the distal end 32 of the cylindrical body 30 (e.g., reversedlocations).

Referring reference to FIGS. 73A-73E and FIGS. 89-90, an embodiment of aclam shell mounting cap 1350 is shown. The clam shell mounting cap 1350is adapted to enclose the cap-bladder assembly 100 according to any ofthe embodiments described hereinabove, but will be discussed withreference to the cap-bladder assembly 100 shown in FIGS. 73A-73E. Theclam shell mounting cap 1350 is formed by two (2) clam shell portions1352, 1354 connected by a hinge 1356. The clam shell portions 1352, 1354may be locked together by a locking catch mechanism 1358 to secure thecap-bladder assembly 100 in an interior cavity 1360 in the clam shellmounting cap 1350. The clam shell portion 1352, 1354 are adapted toengage a flange (not shown in FIGS. 89-90) on the distal end 32 of thecylindrical body 30, such as the enlarged end flange or rim 440 as shownin FIG. 73D as an example. Thus, in one embodiment, the clam shellmounting cap 1350 may be used to secure the cap-bladder assembly 100 tothe end flange or rim 440 shown, for example, in FIGS. 73D-73E. The clamshell portions 1352, 1354 are adapted to engage the end flange or rim440 and seat the end flange 1290 in the annular recess 450 in agenerally fluid-tight manner. In a variation of the foregoing shown inFIG. 91, a split mounting ring 1362 may be used to directly secure thecap-bladder assembly 100 to the distal end 32 of the cylindrical body 30such as by directly securing the end flange 1290 in the annular recess450 in a generally fluid-tight manner. The split mounting ring 1362 mayhave the typical configuration of a split mounting ring used to secure alid to a conventional 55 gallon drum. As a further alternative, thesplit mounting ring 1362 may be used to secure the clam shell mountingcap 1350 shown in FIGS. 89-90 to the end flange or rim 440.

Referring to FIG. 92, a front-loading pressure jacket structure 30″ isshown. This front-loading pressure jacket structure 30″ is alsoexhibited in FIG. 32 of U.S. Pat. No. 7,563,249 to Schriver et al.; theentirety of this patent is incorporated herein by reference. Thefront-loading pressure jacket structure in this Schriver et al. patentcomprises a syringe retaining member that may also be used to secure thecap-bladder assembly 100, such as the embodiment shown in FIGS. 73D-73Eof the present application, to the pressure jacket structure describedin the Schriver et al. patent. In particular, FIG. 92 shows a fluidinjector faceplate 18″ having a pair of outward extending support arms90″, 92″ supporting a syringe retaining member 106″ that may be used tosecure the cap-bladder assembly 100 to the distal end 42″ of a pressurejacket 32″. In certain embodiments disclosed in the foregoing Schriveret al. patent, the distal end 42″ of the pressure jacket 32″ is beveledand the end flange 1290 on the cap body 104 of the cap 102 in thecap-bladder assembly 100 may include an oppositely beveled portion (notshown) to mate with this beveled distal end on the pressure jacket 32″.Other embodiments disclosed in the Schriver et al. patent do not havesuch a beveled distal end on the pressure jacket 32″ and nomodifications are thereby needed to the end flange 1290.

Referring to FIG. 93, another embodiment is shown for securing thecap-bladder assembly 100 to the distal end 32 of the cylindrical body30. As in previous embodiments, the cap-bladder assembly 100, such asthe embodiment shown in FIGS. 73A-73E of the present application, isused to describe the concepts and features shown in FIG. 93 and the useof this embodiment of the cap-bladder assembly 100 is for exemplarypurposes only. The distal end 32 of the cylindrical body 30 comprises anend flange 1370. A retaining groove 1372 is formed between the endflange 1370 and a proximal flange 1374 on the cylindrical body 30. Athreaded mounting collar 1376 is seated for rotation in the retaininggroove 1372 and comprises internal threads 1378 adapted to engageexterior threads 1380 provided on the outer surface or circumference ofthe end flange 1290 on the cap body 104 of the cap 102 of thecap-bladder assembly 100. One or more anti-rotation keys 1382 may beprovided on the end flange 1370 and located to engage corresponding keyslots 1384 within the end flange 1290 on the cap body 104 of the cap 102of the cap-bladder assembly 100. In use, the end flange 1290 is seatedon the end flange 1370 on the distal end 32 of the cylindrical body 30so that the anti-rotation keys 1382 are seated into the correspondingkey slots 1384 within the end flange 1290 on the cap body 104. Thisplaces the exterior threads 1380 on the end flange 1290 on the cap body104 of the cap 102 in engagement with the interior threads 1378 in thethreaded mounting collar 1376 and rotation of the threaded mountingcollar 1376 in the retaining groove 1372 causes the exterior threads1380 on the end flange 1290 to thread into threaded engagement with theinterior threads 1378 in the threaded mounting collar 1376 and securesthe cap-bladder assembly 100 to the end flange 1370 on the distal end 32of the cylindrical body 30. If desired, a receiving annular recess,similar to annular recess 450 shown in FIG. 73D-73E may be provided inthe end flange 1370, with the end flange 1290 on the cap body 104 of thecap 102 secured in the annular recess in a generally fluid-tightcondition by the threaded engagement between the threaded mountingcollar 1376 and the exterior threads 1380 on the end flange 1290.

Referring to FIG. 94 and FIGS. 73A-73E, another embodiment is shown forsecuring the cap-bladder assembly 100 to the distal end 32 of thecylindrical body 30. As in previous embodiments, the cap-bladderassembly 100, such as the embodiment shown in FIGS. 73D-73E of thepresent application, is used to describe the concepts and features shownin FIG. 94 and the use of this embodiment of the cap-bladder assembly100 is for exemplary purposes only. In this embodiment, an over-centerclamp assembly 1390 is mounted to the cylindrical body 30 as illustratedand is used to secure the cap-bladder assembly 100 to the distal end 32of the cylindrical body 30. In this embodiment, the end flange 1290 onthe cap body 104 of the cap 102 is secured in the annular recess 450 ina generally fluid-tight seal by the engagement of the clamp assembly1390 with the cap body 104 of the cap 102. A suitable mechanism for useas the over-center clamp assembly 1390 is found in U.S. Pat. No.1,951,559 to Pyott which discloses a dual clamp assembly for use as theclamp assembly 1390 and the Pyott clamp assemblies may be provided onopposite sides of the cylindrical body 30 to engage on opposing sides ofthe threaded end connector 112 of the distal discharge conduit 110 onthe cap body 104 of cap 102.

Referring to FIGS. 95-97 and additional reference to FIGS. 72A-72B andFIG. 75, the cap-bladder assembly 100 may be provided in a gangedformat, such as dual format as illustrated. In the ganged format, two(2) cap-bladder assemblies 100 may be joined together by a connectingappendage of material 1396 connecting the cylindrical portions 114 ofthe cap bodies 104 of the two (2) caps 102. As FIG. 97 shows, the fixedarm 434 of the clamping assembly 432 may be formed with two (2) extendedleg segments 1398 to accept the elongated form of the two (2) gangedcap-bladder assemblies 100, and the swing arm 436 is used to fix the two(2) ganged cap-bladder assemblies 100 in the clamping assembly 432.Other features of the clamping assembly 432 were described previously inthis disclosure. As an alternative, the fixed arm 434 with the two (2)extended leg segments 1398 may be slidably connected to the distal end430 of the fluid injector housing 18 so that the two (2) gangedcap-bladder assemblies 100 may be axially-loaded onto the distal end 430of the fluid injector housing 18, with the fixed arm 434 being slid intoengagement with the two (2) ganged cap-bladder assemblies 100 andsecuring the same to the distal end 430. In this variation, the swingarm 436 remains connected to the distal end 430 of the fluid injectorhousing 18 and may be pivoted to secure the two (2) ganged cap-bladderassemblies 100 in the clamping assembly 432.

Referring to FIG. 98, in another embodiment, the cap-bladder assembly100 may be secured by any suitable connecting arrangement between thecylindrical portion 114 of the cap body 104 of the cap 102 and a flangeor lip 1400 on the distal end 32 of the cylindrical body 30. As analternative, a simple bayonet tab-slot connection may be providedbetween the cylindrical portion 114 and the distal end 32 of thecylindrical body 30. In FIG. 98, an inflatable or expandable seal 1402is provided internally within the cylindrical portion 114 of the capbody 104 and extends around the circumference of the distal end 32 ofthe cylindrical body 30 when the cap 102 is seated onto the distal end32. The expandable seal 1402 may be inflated or expanded by connectionto an external compressed air source or with materials that change shapewhen voltage or current are applied. The mechanism for expanding theseal 1402 may controlled by the control features of the fluid injector12.

Referring to FIG. 99, the distal discharge conduit 110 and luerconnector 112 on the cap body 104 of the cap 102 may be formed as partof a rotatable protector cap 1410 that is rotatably disposed on the capbody 104. The cap body 104 defines a discharge port or opening 1412 thatmay be aligned with the distal discharge conduit 110 to permit fluidflow into and from the bladder 1140 in the cap-bladder assembly 100during normal operation. When the use of the cap-bladder assembly 100 iscomplete and it is desired to remove the cap-bladder assembly 100 fromthe distal end 32 of the cylindrical body 30, the protector cap 1410 maybe rotated on the cap body 104 to a position wherein the discharge portor opening 1412 is unaligned with the distal discharge conduit 110. Thisunaligned position or orientation prevents fluid spillage as thecap-bladder assembly 100 is removed from the cylindrical body 30. Incertain embodiments, a rotational action is used to attach and removethe cap-bladder assembly 100 from the distal end 32 of the cylindricalbody 30, and this rotational motion may be used as part of the action inrotationally positioning the discharge port or opening 1412 in theunaligned orientation.

Referring to FIGS. 100-101, in another embodiment, the bladder syringe20 has a cylindrical body 30 that is split along its sidewall to form anupper portion or half 1420 and a lower portion or half 1422. The upperand lower portions 1420, 1422 define opposing end flanges 1424, 1426,respectively A pair of bladders 1140 is disposed between the opposingend flanges 1424, 1426, and the bladders 1140, according to any of theembodiments described previously, are sandwiched between the opposingend flanges 1424, 1426. In particular, the outer circumferential rib1142 on the bladders 1140 is formed to be sandwiched between theopposing end flanges 1424, 1426. A plurality of clamp elements 1428 isprovided around the opposed end flanges 1424, 1426 and the clampelements 1428 are adapted and secured to the respective opposing endflanges 1424, 1426 axially relative to one another, thereby securing theback-to-back bladders 1140 between the end flanges 1424, 1426 in agenerally fluid-tight manner. The upper or distal bladder 1140 isprovided with an integral discharge conduit 110 supporting an endconnector 112 such as a luer fitting which is formed as part of membraneportion 1146 of the bladder 1140. The cap body 104 of the cap 102defines a central opening 1430 adapted to receive the discharge conduit110. The cap body 104 may be secured to the distal end 32 of thecylindrical body 30 by any suitable connection arrangement found in thisdisclosure or may be permanently connected to the distal end 32.Moreover, in this embodiment, the cap body 104 may be formed as part ofthe upper or distal portion 1420 of the cylindrical body 30.

The embodiment of the bladder syringe 20 shown in FIGS. 100-101comprises two (2) back-to-back bladders 1140 that limits the stretch ofeither of the bladders 1140 to approximately half the stretch requiredof in all the previously described embodiments wherein only one (1)bladder 1140 is provided. In particular, in use, a piston element (notshown in FIGS. 100-101 but may be any one of the vacuum-generatingplunger elements 50 connected to a piston elements 14 as describedpreviously) may move distally in the throughbore 37 of the cylindricalbody 30 until the plunger element 50 contacts the back-to-back bladders1140. The plunger element 50 expands both bladders 1140 and pushes thedischarge conduit 110 into engagement in the central opening 1430 in thecap body 104 and which is adapted to receive and secure the dischargeconduit 110 in engagement with the cap body 104. The engagement betweenthe discharge conduit 110 and the central opening 1430 may be a frictionfit connection or any suitable mechanical connection may be provided,and may include or provide a generally-fluid tight seal between thedischarge conduit 110 and the central opening 1430. Once the dischargeconduit 110 is seated in the central opening 1430, the upper bladder1140 is stretched distally as shown FIG. 101. The plunger element 50 maybe withdrawn proximally in the throughbore 37 to draw a vacuum behindthe second or proximal bladder 1140 and fill the space formed betweenthe bladders 1140 with fluid as shown schematically in FIG. 101. Thefluid enters the space between the bladders 1140 via the dischargeconduit 110 and the end connector 112, which is connected to an externalsource of fluid (not shown).

Referring to FIGS. 102-105, two (2) embodiments of the cap-bladderassembly 100 are shown made by a multi-shot injection molding procedure.In these multi-shot injection molded components, it is generally desiredto have the top part or surface of the elastomeric bladder 1140 and thebottom part or surface of the cap body 104 of the cap 102 to havecorresponding shapes. However, in certain embodiments describedhereinabove, the membrane portion 1146 of the bladder 1140 may beformed, for example, with a convoluted shape, such as the W-shapedconvoluted central well portion 1148 shown in FIG. 6. In typicalinjection-molding methods, the convoluted shape in the central wellportion 1148 would also require that the harder plastic cap body 104have the same convoluted shape. Such a convoluted shape for the cap body104 of the cap 102 may not be desirable as pockets are formed thatcannot be easily purged of air prior to a fluid injection procedure.

In FIGS. 102-105, the cap body 104 of the cap 102 is formed with a largecentral opening 1450 in the discharge conduit 110 which is disposed overthe convoluted central well portion 1148 of the bladder 1140. This opensection in the hard plastic forming the cap body 104 is covered by asecondary cap element 1452 secured to the discharge conduit 110 afterthe multi-shot injection molding procedure is completed for forming thecap body 104 and the bladder 1140 as an integral unit. During themulti-shot injection molding procedure, the convoluted central wellportion 1148 of the bladder 1140 may be supported by the mold throughthe open section formed by the opening 1450 during molding, thesecondary cap element 1452 may be applied to the discharge conduit 110after molding is complete. As an example, the secondary cap element 1452may be secured to the discharge conduit 110 by a suitable medical gradeadhesive, ultrasonic welding and like connection methods. The secondarycap element 1452 may be formed to have a luer-type end connector 112 asin previous embodiments. While not described in detail hereinabove, thecircumferential connection between the cap body 104 and the bladder 1140in FIGS. 102-103 may be similar to that shown in FIG. 47B, describedpreviously, wherein the bladder 1140 is shown connected to the open endof an inner liner 194; the cap body 104 takes the place of the innerliner 194 in the present embodiment, and the outer circumferential rib1142 of the bladder 1140 is molded to wrap around the outercircumferential edge 1454 of the cap body 104 in this embodiment.

The secondary cap element 1452 has a shape that is more conducive forair purging and there is no longer a need for the cap body 104 to beformed with a shape to match the convoluted or the shaped centralportion of the bladder member 1148 found in several embodiments of thebladder 1140 discussed previously. Another advantage of the secondarycap element 1452 is that the bladder 1140 cannot become bonded to thecap body 104, intentionally or unintentionally, during the moldingoperation, facilitating the easy release of the bladder 1140 from thecap body 104 during operation of the bladder syringe 20 when a vacuum isdrawn behind the bladder 1140 in the cylindrical body 30. The secondarycap element 1452 or the cap body 104 may also include an elastomericseal (not shown) such that the secondary cap element 1452 could besnap-fitted onto the discharge conduit 110 on the cap body 104 andremain sealed without requiring the application of an adhesive or otherbonding process. In FIGS. 104-105, the elastomeric material forming thebladder 1140 covers the outer circumference of the cap body 104 in thesame manner as in FIGS. 102-103, but further comprises radial appendages1456 that connect to an annular collar 1458 disposed around thedischarge conduit 110. The annular collar 1458 can be used as part of aseal between the secondary cap element 1452 and the discharge conduit110, as shown in FIG. 105.

Referring to FIGS. 106-109, additional embodiments of the plungerelement 50 are shown respectively in FIGS. 106 and 108, which includemodified embodiments of the seal ring 88 described previously inconnection with FIGS. 10A-10B and FIGS. 11A-11D. As described inconnection with FIGS. 10A-10B and FIGS. 11A-11D, the seal ring 88provides a generally fluid-tight or leak proof seal with the interiorwall 36 of the cylindrical body 30. The plunger element 50 in FIGS. 106and 108 has the same general configuration as the plunger element shownin FIGS. 10A-10B with certain distinguishing features as describedherein. Other than the following differences, the features of theplunger element 50 in FIGS. 106 and 108 and the plunger element 50depicted in FIGS. 10A-10B are similar and have been previously describedin connection with FIGS. 10A-10B. In FIGS. 106 and 108, the plungerelement 50 lacks the porous plug 134 and is depicted with a radialpassageway 66 in the same manner as the plunger element 50 shown in FIG.9. Additionally, the plunger element 50 is depicted without a sensor204. However, the sensor 204, in any of the forms discussed previously,may be provided coaxially in the plunger element 50. Further, the distalportion 52 the plunger element 50 does not define a distal circularrecess 138 that surrounds a flat nub or ledge 139, as shown in FIGS.10A-10B. In the present embodiment, the distal portion 52 is generallydome-shaped in cross-section as illustrated and defines a central wellor recess 1460 surrounded by a rounded annular portion 1462 and thisparticular configuration has also been found to work well with thebladder 1140 shown, for example, in FIG. 6 having a membrane portion1146 with a W-shaped convoluted central well portion 1148 because theinteraction between the central well or recess 1460 surrounded by therounded annular portion 1462 and the extra material present in theW-shaped convoluted central well portion 1148 maintains the bladdermaterial aligned in the cylindrical body 30 during expansion/elongationof the bladder 1140 and thereby enables greater stretching or filling ofthe bladder 1140.

In FIGS. 106-107, the seal ring 88 is shown according to anotherembodiment. The seal ring 88 in this embodiment is a double lip seal1464 comprising two (2) axially opposed lips, comprising an upper ordistal lip 1466 and a lower or proximal lip 1468. The double lip seal1464 provides dynamic sealing when either vacuum or pressure is presentin the area between the bladder 1140 and the plunger element 50, (e.g.,the bladder “cavity”). During filling of the bladder 1140, a vacuum isgenerated which pulls the lower lip 1468 out against the interior wall36 of the cylindrical body 30 with a force proportional to the vacuumlevel generated. During injection the upper lip 1466 is pushed againstthe interior wall 36 providing increased sealing force proportional tothe pressure generated. The upper lip 1466 also contains a radial lipportion 1470 which covers the gap between the outer circumference of theplunger distal portion 52 and the interior wall 36. Pressure forces thislip portion 1470 against the surface of the plunger distal portion 52and prevents the bladder 1140 from extruding into this gap. The lipportion 1470 also protects the bladder 1140 from extruding into theinlet port 92 to the radial passageway 66 leading to vent path 90 (seeFIGS. 8-9), when the inlet port 92 is positioned below the interfacebetween the lip portion 1470 and the bladder 1140. To allow air to reachthe inlet port 92 during air purging, the lip portion 1470 does not sealagainst the plunger distal portion 52; only during pressurization doesthe lip portion 1470 seal against the plunger distal portion 52.Suitable materials for the seal ring 88 include, but are not limited to,urethane, silicone, or EPDM. In use, it is desirable for the upper lip1466 to also provide a seal under vacuum, which can eliminate the needfor the lower lip 1468 and this embodiment of the seal ring 88 isdepicted in FIGS. 108-109. This alternative construction minimizes theamount of air that may be present below the bladder 1140 following airpurging. In the implementation of the seal ring 88 depicted in FIGS.108-109, air trapped between the upper and lower lips 1466, 1468 is notbe able to be evacuated during the air-purge cycle. Alternatively, theseal ring 88 according to the embodiments in FIGS. 106-109 may beovermolded onto the plunger distal portion 52, which eliminates any gapbetween the plunger distal portion 52 and the seal ring 88 that is apotential pinch point for the bladder 1140. The seal rings 88 describedpreviously in this disclosure such as in connection with FIGS. 11A-11Dmay also be overmolded onto plunger distal portion 52. FIG. 109A andFIG. 109B show similar but the seal ring 88 shown in FIG. 109B furthercomprises a compressible curl element 1472 on the upper lip 1466, whichcauses the plunger element 50 to have an increased coefficient offriction. The plunger element 50 having the curl element 1472 has theadvantage of restricting the rate that the bladder 1140 is fed outwardor bridges outward toward the interior wall 36 of the cylindrical body30, but does not interfere with the bladder 1140 as it expands downwardfrom the cap body 104 of the cap 102. By restricting the rate that thebladder 1140 feeds across the bridging area between the plunger distalportion 52 and the interior wall 36 of the cylindrical body 30, thebladder 1140 is distributed to the interior wall 36 at a slower rate fora given volume and retains extra material for the last portion of thebladder 1140 that is filled with fluid and, further, there is lessstrain on the bladder 1140 at a given maximum fill volume. The curlelement 1472 compresses at the end of the delivery cycle and does notaffect the ability to deliver all of the fluid in the bladder 1140 asthe plunger element 50 is advanced to the zero ml remaining position.

Referring to FIGS. 110A-110C, the ability for the elastic bladder 1140to effectively fill when the plunger element 50 is drawn back isdependent on several factors. One factor is the shape of the bladder1140, wherein a “taller” or more convoluted bladder 1140 contains morematerial at that same thickness compared to flatter geometries whichreduces the amount of strain on the material as it is drawn to extendedvolumes. A second factor is the interface between the bladder 1140 andthe plunger element 50. If the bladder 1140 has a high resistance tosliding down the plunger distal portion 52 it will delay the eventual“playing out” of the bladder 1140 toward the interior wall 36 of thecylindrical body 30, and allows for more material at a lower strainlevel at extended volumes increasing the potential fill volume of thebladder 1140. A further factor is the thickness profile of the bladder1140. A bladder 1140 with a non-uniform cross-section has the advantageof adjusting the strain at different areas of the fill. Another factoris the strain on the bladder 1140 during filling. If compressive forcesact on the bladder 1140, the compressive forces tend to cause thebladder 1140 to pleat reducing the potential fill volume of the bladder1140. The modulus of elasticity of the bladder 1140 is another factor.As the modulus increases, the pull on the bladder 1140 becomes alltension, and not tension and compression, which reduces the chances ofpleating. Finally, the lift-off area of bladder 1140 on the plungerelement 50 is another performance factor. If the bladder 1140 has alarge unsupported section because the shape of the plunger element 50 istoo steep and too far away from the interior wall 36 of the cylindricalbody 30, the radial strain could be too high compared to the axial(circumferential) strain and this difference could lead to undesirablepleating or puckering, which is essentially the folding over or togetherof elastomeric material forming the bladder 1140.

Based on experiments conducted on the shapes of the bladders 1140 andplunger distal portions 52 shown in FIGS. 110A-110C, it is known thatthe bladder 1140 and the plunger distal portion 52 shown in FIG. 110Aconsistently do not develop pleating when a vacuum is drawn and thebladder 1140 fills with fluid. The bladder 1140 and the plunger distalportion 52 shown in FIG. 110A are also depicted in FIG. 10A discussedpreviously. The bladder 1140 and the plunger distal portion 52 shown inFIG. 110B and depicted in FIGS. 106 and 108 also consistently do notdevelop pleating when a vacuum is drawn and the bladder 1140 fills withfluid. The bladder 1140 in FIG. 110B comprises a thickened centralportion 1500 and a nipple portion or feature 1502 that is disposedopposite the central well or recess 1460 surrounded by the roundedannular portion 1462 of the plunger distal portion 52. In contrast, thebladder 1140 and the plunger distal portion 52 shown in FIG. 110Cconsistently develop pleating when a vacuum is drawn and the bladder1140 fills with fluid, and the bladder 1140 in FIG. 110C has a nippleportion or element 1502 that opposes a central well or recess 1460surrounded by the rounded annular portion 1462 of the plunger distalportion 52. However, the distal portion 52 in FIG. 110C is steeper thanthose shown in FIGS. 110A-110B and, likewise, the central well or recess1460 is deeper. From the testing of the above combinations of bladders1140 and plunger distal portions 52, several factors are known tocontribute to increased or decreased chances of pleating, including: (1)steeper angles for the plunger distal portion 52 lead to higher chancesof pleating; (2) longer distances d (shown in FIG. 110C) to theinflection point of the plunger distal portion 52 reduces chance ofpleating; (3) other factors affecting pleating include bladderthickness, modulus of elasticity, plunger shape (e.g., liner, concave,convex, or a combination of the foregoing shapes), and surfacefinish/lubricity of the plunger distal portion 52. From the experimentsconducted on the shapes of the bladders 1140 and plunger distal portions52 shown in FIGS. 110A-110C, the inventors have concluded that onepleating indicator (PI) is a low or negative value of hoop stress in thebladder 1140 divided by fiber strain ratio of the bladder 1140, (e.g.,PI=Hoop Stress/Fiber Strain Ratio). A negative value indicates that oneof the strains, mainly the hoop strain, in the ratio is compressive.Finite Element analysis can be used to determine the PI and to optimizebladder 1140 and plunger element 50 shapes using the PI.

FIG. 111 is a schematic cross-sectional view of a generalized bladdersyringe 20 comprising a cylindrical body 30 having a central axis L, aplunger distal portion 52 of the plunger element 50, and a bladder 1140,and will be referenced to describe the phenomena associated with theexpansion, movement, playing out, drawing out, or deployment of thebladder 1140 onto the interior wall 36 of the cylindrical body 30. FIG.111 shows the process of this deployment. In operation, the plungerelement 50 is drawn downward in the cylindrical body 30 and the bladder1140 is drawn outward from the plunger distal portion 52 to the interiorwall 36 of the cylindrical body 30. The seal ring 88, describedpreviously and associated with the plunger element 50, forms a sealbetween the plunger distal portion 52 and the interior wall 36 tomaintain a low, negative, or vacuum pressure, as represented by arrowP2, between the bladder 1140 and the plunger element 50 and the interiorwall 36 of the cylindrical body 30.

To facilitate the understanding of the expansion that the materialforming the bladder 1140 undergoes in successful deployment of thebladder 1140, the bladder 1140 may be considered to be divided into four(4) material regions, segments, states, or zones, 2100, 2200, 2300,2400. The first material region 2100 is the material held against theinterior wall 36 of the cylindrical body 30 and, during the depictedexpansion, this bladder material has already been deployed and “pushed”against the interior wall 36 of the cylindrical body 30 by internalpressure in the bladder 1140, as represented by arrows P1. Thefrictional force between the interior wall 36 and the first materialregion 2100 is sufficient such that it does not move or stretchsignificantly once deployed against the interior wall. The next area,which is a bridging area or region 2200 does not have contact witheither the interior wall 36 or the plunger element 50. This secondmaterial region 2200 forms a complex three-dimensional curved surfacedetermined by the difference of the two (2) pressures P1 and P2 on bothsides thereof and the fiber and hoop stresses on the material. The thirdmaterial region, section, or zone 2300 is the deploying material that isbeing pushed against the plunger distal portion 52 by the differencebetween pressures P1 and P2. This deploying bladder material 2300 isstretched as it moves over the plunger surface toward the first materialregion 2100, with this motion being resisted by the frictional forcecoming from this pressure pressing or holding the bladder materialagainst the plunger distal portion 52. The fourth material region,section, or zone 2400 is a “reservoir” or reserve of bladder materialthat has not yet been stretched to a significant degree. The fourthmaterial region 2400 may or may not be contacting the plunger distalportion 52. As the deploying material of the third material region 2300moves from the plunger element 50 to the interior wall 36, material ispulled from the reserve material forming the fourth material region 2400to continue the deployment process. As may be seen in the variousembodiments herein, the provision of some reserve material can beaccomplished by various shapes and/or thicknesses in the design of thebladder 1140.

As mentioned previously, certain factors can affect the deployment andthe expansion properties of the bladder 1140, and various embodiments ofthe bladder syringe 20 have been described previously which yieldsuccessful operation of the bladder syringe 20 in practice. Some ofthese factors affecting the expansion properties or characteristics ofthe bladder 1140 will now be described in further detail. One factor isthe material properties or characteristics of the material forming thebladder 1140, including durometer, the time dependent stress-strainrelationship including hysteresis effects, surface adhesion or surfaceenergy, plastic relaxation or yield rates, the initial bladder shapeincluding thickness, and the percentage elongation at which the materialruptures, and/or the rupture strain or stress. The shape of the bladder1140 is also a relevant property, as shown by the variety of bladdershapes or embodiments disclosed herein.

Another factor affecting the expansion properties or characteristics ofthe bladder 1140 include relevant characteristics associated with theplunger element 50, including for example, the type of material and allthe associated material properties, the surface adhesion or surfaceenergy, and the surface texture. The shape of the face of the plungerdistal portion 52 is one of the factors relevant to the location of thetransition between the deploying material in the third material region2300 and the bridging material in the second material region 2200. Thesurface of the plunger distal portion 52 may be considered to be dividedinto different surface segments as represented by reference charactersF1-F4 in FIG. 111. The first surface segment F1 is not generallyinvolved in interacting with the bladder 1140 during deployment orexpansion. The second surface segment F2 is the segment from which thebladder 1140 “lifts” relatively early in the deployment or expansionprocess. The third surface segment F3 is the segment that generallyremains in contact with the bladder 1140 during the entire deployment orexpansion process, although the point at which the bladder 1140lifts-off can change somewhat during the deployment or expansion processas the material generally thins during deployment/expansion. The fourthsurface segment F4 supports the reserve bladder material of the fourthmaterial region 2400. The lengths and angles between the second andthird surface segments F2 and F3 and the interior wall 36 are relevantto determining the deployment or expansion properties and the stabilityof the deployment/expansion. The above-mentioned surface segments of theplunger distal portion 52 may be of the same shape as each other and bemade of the same material and, thus, the distinction between thesegments is purely based on the behavior of the bladder 1140 duringdeployment. Alternatively, there may be specific changes in angles,surface texture, or surface material to affect the interaction of thesurface segment(s) with the bladder 1140 to promote the desireddeployment. For example, an elastomer or some higher friction materialmay be insert-molded onto the plunger distal portion 52 in the thirdsurface segments F3. As can be seen in FIGS. 110A and 110B, an angledefined by surface segments F2 and F3 approaching 90° is beneficial.Angles greater than 90° have a benefit in resisting pleating/puckeringas described herein, but present a challenge with removal of air,although bladder design shape and thickness can be chosen to mitigatethis effect. In addition or alternatively, the seal ring 88 may bedesigned so that a portion thereof, such as the curl element 1472 shownin FIG. 109B, extends upwards from the seal ring 88 so that the bladdermaterial contacts this portion as it deploys, and the second and thirdsurface segments F2 and/or F3 may occur on the seal surface asillustrated in FIG. 109B.

Another factor affecting the expansion or deployment properties orcharacteristics of the bladder 1140 include material properties of thecylindrical body 30 and properties of the interior wall 36, and includethe type of material and the associated material properties orcharacteristics, for example, the surface adhesion or surface energy andthe surface texture of the interior wall 36. In addition, the existenceof a lubricant or contaminant on or between the bladder 1140 and thesurfaces described above or other components can be a relevant factor.Although a lubricant may be helpful for the operation of the seal ring88, the presence or effect of a lubricant does not necessarily improveor enhance bladder deployment or expansion, as will be discussed herein.

Properties of the deployment or expansion include, for example, thespeed and direction of the movement of the plunger element 50, ambienttemperature, the temperature, viscosity, and other properties of thefluid or gas being pulled or pushed into the bladder 1140, thetemperature of the bladder 1140, and the pressures P1 and P2.Temperature is an especially relevant variable because it affects manyof the material characteristics and surface properties of various systemor device components. If the bladder syringe 20 is being filled from asystem open to the atmosphere, effectively, the highest pressuredifference that P1-P2 can achieve is 1 atmosphere. If the bladdersyringe 20 is being force-filled or externally pressurized, the pressuredifference can be much higher.

Speed of deployment or movement of the plunger element 50 is alsorelevant in affecting the transition of the effective frictional forcefrom that of the static frictional force with periodic or sporadic jumpsto a motion approaching the generally lower dynamic frictional forcethat comes from the almost continuous “walking” of the bladder materialover the plunger element material, as is well known in the art oftribology of sliding elastomeric materials. Speed is also importantbecause sections or segments of the bladder 1140 may be stressed inregions of the stress strain curve in which the plastic deformation rateis comparable to the time of the deployment, causing relatively rapidplastic or non-elastic deformation to occur. Alternatively using aslower deployment speed or periodically stopping the deployment canallow plastic flow or stress relaxation which enables greater elongationto occur at lower forces.

As mentioned previously, FIG. 111 shows a bladder 1140 in a partiallydeployed or expanded state. Because the bladder 1140 is generally thincompared to its other dimensions, each minute surface element or volumeelement of the bladder 1140 can be considered to be or modeled as acurved sheet having three (3) stresses or forces acting on it. The firststress or force is a tangential stress that comes from stretching thebladder 1140 in the radial or axial direction. This stress is in theplane illustrated in FIG. 111 and tangential to the bladder surface andis called a radial or fiber stress. Because of the circular symmetry,each bladder element can also be considered to have a circumferentialstress or force which is again tangential to the surface of the bladder1140 but is perpendicular to the plane of FIG. 111 and is called a hoopstress. The third stress or force is perpendicular to the surface of thebladder 1140 and in the plane of FIG. 111. Because plastic generallyacts as an incompressible material, the three (3) strains orcompressions resulting from these forces or stresses conserves thevolume of the material and so are related.

The following discussion references the radial or fiber stress and thecircumferential or hoop stress. The effect of these forces in thepositive direction is to stretch or thin the bladder material as it isdeployed. In addition to the elastic or recoverable deformation orstrain that occurs at stresses below the elastic limit, the bladdermaterial can also plastically (that is non-elastically) deform. Theamount of the non-recoverable or plastic deformation is a function ofthe rate of deformation and the time over which that stress ismaintained.

In the deployment of the bladder 1140, the intent is to move the bladder1140 from its initial shape on or against the plunger distal portion 52to a deployed shape that forms a continuous structurally sound surfaceon the interior wall 36, the plunger element 50, and bridging the regionbetween the plunger distal portion 52 and the interior wall 36. As ageneral explanation of deployment, the increase in fiber length of thebladder 1140 results from moving the plunger element 50 downward, whichcreates a fiber or radial force or stress that causes the bladder 1140to move from the fourth material region 2400 into the deploying bladdermaterial region or third material region 2300. The movement of bladdermaterial in the radial direction in the third material region 2300 isincreased or promoted by the stress or force coming from the bladderbridging region or second material region 2200 and is resisted by thefrictional force of the bladder material in the deploying bladdermaterial region or third material region 2300 as it is pushed againstthe third surface segment F3 by the pressure difference P1-P2, by theincrease in hoop stress required to stretch the bladder materialcircumferentially as it moves radially outward over the third surfacesegment F3, as well as by the generally lower but non-zero stressrequired to pull material from the reservoir fourth material region2400. The frictional resistance force is affected by the factorsmentioned previously, including the pressure difference P1-P2, theinitial shape of the bladder 1140, and the angles of the plunger surfacesegments F4 and F3. The frictional force is also proportional to thecoefficient of friction between the two (2) materials which is affectedby other factors mentioned previously, such as surface energy andtexture and the presence or any lubricant. For proper operation, thefrictional force must be sufficient such that the bladder material isstretched sufficiently thin so that the total initial “load” or mass ofthe bladder material can be deployed onto the surface of the interiorwall 36, over the bridging second material region 2200, and over theplunger distal portion 52 without approaching rupture conditions in thefully deployed or filled condition, with a sufficient design margin.

Once the bladder material leaves contact with the plunger element 50 inthe bridging second material region 2200, the bladder material travelsthrough a three-dimensional arc in space. As it moves, the hoop stressincreases. The shape of the arc is determined by the fiber stress, thehoop stress, and the difference in pressure, P1-P2. The greater thepressure difference, the more the bladder 1140 is pushed into the cornerdefined between the interior wall 36 and the plunger distal portion 52,and yielding a smaller radius R. The larger the fiber stress and, to alesser degree, the larger the hoop stress, the more the bladder 1140 ispulled back towards a straight line between the liftoff point on theplunger element 50 and the contact point on the interior wall 36. Whilethis arc is not a simple cylindrical or curved surface with a singleradius of curvature, it can be more easily discussed in relation to ageneral, average, or median curvature R. With a small radius ofcurvature R, the bladder material moves through an arc that is moretightly received into the corner between the interior wall 36 and theplunger distal portion 52. An arc with a larger radius of curvature R isa longer, gentler curve of material.

When the bladder material, which is under stress, reaches the interiorwall 36, it contacts the interior wall 36 and effectively pushes out theair from between it and the interior wall 36, given that P1 is greaterthan P2. There is now a frictional force established between the bladdermaterial and the interior wall 36, such that the bladder 1140 is heldagainst the interior wall 36. Under desired operating conditions, eventhough the stress required to continue deployment of the bladder 1140generally increases during deployment, the increased stress transmittedthrough the bridging second material region 2200 to the interface withthe first material region 2100 is not sufficient to overcome thefrictional force holding the bladder 1140 to the interior wall 36 in thefirst material region 2100. Lubrication could reduce this frictionalforce, but given the significant pressure difference P1-P2, there iseffectively no motion of the bladder 1140 over the interior wall 36 oncecontact is established, even with a modest amount of lubricant. The endresult of the foregoing process is that the bladder 1140 is deployed sothat it is frictionally attached to the interior wall 36 of thecylindrical body 30, bridges to the plunger element 50, and covers theplunger distal portion 52, with the maximum stress, maximum thinning,and/or maximum strain of the bladder material being below the rupturelimits of the bladder material and with sufficient margin of safety ordesign for maintenance of integrity over the specified dwell or filltime of the design, as will be appreciated by those skilled in the art.

As an example of the foregoing, it was previously noted that the bladder1140 and the plunger distal portion 52 shown in FIG. 110C consistentlydevelops pleating when a vacuum is drawn and the bladder 1140 fills withfluid. The bladder 1140 shown in FIG. 110C routinely develops pleats,puckers, or gathers, meaning that the deployment of the bladder 1140from the bridging second material region 2200 to the wall-located firstmaterial region 2100 becomes uneven as viewed rotationally around thecircumference of the deployed or expanded bladder 1140. One way tounderstand this occurrence is that the hoop stress generated by thedeployment process is too low in relationship to the radius of curvatureR in the bridging second material region 2200 given the pressuredifference and the fiber stress to keep the deployment uniform. Anegative hoop stress, that is a compressive hoop stress, promotespleating. Another aspect of the cause of pleating or puckering relatesto the angles of the plunger surface segments F2, F3, and F4 and thedistances of the surfaces from the interior wall 36.

Another way to analyze mechanical system is to consider energyminimization. A system under equilibrium will generally adopt a shapethat has the lowest overall potential or stored energy, even though someparts of the system may have higher energies than others. In this case,energy is stored as “spring” or elastic energy in the plastic. Pleatingor puckering occurs because there is less energy (stress) in a region ofthe deploying or bridging material region 2200, which adopts asignificantly larger radius of curvature R than another region of thedeploying or bridging second material region 2200 having a smallerradius of curvature R. In conditions where the angle between theinterior wall 36 and the plunger surface segments F2 and F3 are reducedsignificantly below 90°, as in FIG. 110C, there is also an energyminimization that comes from a shorter bridging length, from “cuttingthe gap short”, that is leaving the surface of the plunger distalportion 52 at a point closer to the central axis L and attaching to theinterior wall 36 at a point higher up towards the fill point of thebladder syringe 20. Although this requires that additional hoop stressoccurs in segments of the bladder 1140 between the pleats because thesurface path length of the bladder 1140 is increased circumferentiallyas it is moved up and down between the regions of different curvature,this is more than balanced energetically by the sections of the bladder1140 that have reduced fiber stress because the radius of curvature R ofthat region is increased. When the net energy balance favorspleating/puckering, pleating/puckering occurs. Given all of the factorsat play including those mentioned previously, finite element analysis isa suitable tool to enable one skilled in the art to determine specificgeometries that work successfully with selected materials or to choosematerials that can operate successfully with suitable geometries.Another potential source of uneven deployment comes from the lowdurometer or stretchiness of the bladder material itself. This phenomenacan be thought of as the opposite of strain hardening that occurs withresins like PET during stretch blow molding. With the bladder 1140, as asection is stretched, the bladder 1140 thins. For a constant force, thestress increases as the material thins. However, with plasticdeformation of a soft material, as the stress increases, it plasticallydeforms more quickly, so an increasing or even runaway thinning orself-reinforcing or propagating phenomena can occur. In the bladdersyringe 20, the failure mode is a rupture of the bladder 1140. Pleatingor puckering can lead to failure because the bladder deployment isnon-uniform, increasing the thinning of the bladder material in thespace between the pleats, as mentioned previously.

In the context of the generalized embodiment of the bladder syringe 20shown in FIG. 111, rupture occurs when the stress of the bladdermaterial, most commonly in the bridging second material region 2200,exceeds the rupture stress of the bladder material. As mentionedpreviously, this stress is affected by the friction of the bladdermaterial in the third material region 2300 on the plunger surfacesegment F3, which is affected by the pressure difference P1-P2 and thestress. Rupture is more likely to occur when the reserve bladdermaterial in the fourth material region 2400 has been used up before thedesired fill volume has been reached, so that the force on thecentermost or axial element of the bladder 1140 increases, therebycausing the stresses throughout the entire deployment process toincrease similarly. In addition, rupture can occur when the stress ofdeployment increase because the movement of the bladder material in orthrough the third material region 2300 is increased for other reasons,such as increased coefficient of friction or pressure difference.Rupture is most likely to initiate at an imperfection, inclusion, defector other segment or region in the bladder 1140 with a slight weakeningor stiffening (due to stress concentrations) of the bladder material. Anadditional condition that can lead to rupture is the presence of toomuch lubrication on plunger segment surface F3. If this occurs, thebladder material is not stretched sufficiently thin at the beginning ofthe deployment and so uses up the bladder thickness and/or reservematerial such that by the end of the deployment, the bladder materialreaches such a thin state that rupture becomes more likely.

The material and the speed of the fill can affect the efficiency of thedeployment of the bladder 1140 from the plunger element 50 to theinterior wall 36 as it transitions through the bridging second materialregion 2200. Generally, materials with a lower modulus of elasticity(such as a Thermoplastic Elastomer (TPE) with a shore durometer of 5Aand an elongation of 1800%) can expand or deploy across the bridgingsecond material region 2200 without creating too large of a radius ofcurvature R. These materials fill easily, but experience has shown thatit is preferable to fill at a slow rate, so as not to “overdrive” thematerial expansion. For example, a fill rate of 6 to 8 ml/S isacceptable for a 200 ml syringe with a stroke length of approximately4.5 inches. It has also been observed that a pause in the fill cycleappears to improve the maximum fill amount. Materials, such silicone,yield at a higher stress but generally do not fill as well because, withthe high fiber stress, these material have a larger radius of curvatureR and can even completely lift off the plunger distal portion 52 and notfill any further at the point where the maximum stress is sufficient toovercome the pressure difference P1-P2. Once lifted off, the bladder1140 will not stretch or fill any further. The foregoing discussionillustrates one of the problems with using a vacuum to fill, which isthe pressure P2 cannot go lower than 0 absolute pressure, and one of thebenefits of filling with a pressure P1 that is greater than atmosphericpressure.

FIG. 109A and FIG. 109B show similar seal rings 88, but the seal ring 88shown in FIG. 109B further comprises a compressible curl element 1472 onthe upper lip 1466, which causes the plunger element 50 to have anincreased coefficient of friction. The plunger element 50 having a sealring 88 with the curl element 1472 has the advantage of acting as therestricting plunger surface segment F3 discussed in connection with FIG.111 and restricting the rate that the bladder 1140 is fed outward orbridges outward toward the interior wall 36 of the cylindrical body 30,but does not interfere with the bladder 1140 as it expands downward fromthe cap body 104 of the cap 102. By restricting the rate that thebladder 1140 feeds across the bridging area between the plunger distalportion 52 and the interior wall 36 of the cylindrical body 30, thebladder 1140 is distributed to the interior wall 36 at a slower rate fora given volume and retains extra material for the last portion of thebladder 1140 that is filled with fluid and, further, there is lessstrain on the bladder 1140 at a given maximum fill volume. Such a designalso reduces the likelihood of pleating because the length of thebridging second material region 2200 is significantly reduced. The curlelement 1472 compresses at the end of the delivery cycle and does notaffect the ability to deliver all of the fluid in the bladder 1140 asthe plunger element 50 is advanced to the zero ml remaining position.Furthermore, by a selection of the choice of the shape and properties ofseal ring 88 and the plunger distal portion 52, the bladder 1140 can bestretched in two stages, first by friction with the surface of theplunger distal portion 52 and then secondarily by friction with the sealring 88. There can be a bridging section between the two stages, or thebladder 1140 can move from one stretching or deployment stage into theother. In the first case, it could be said that there are two (2)bladder material regions 2300, 2200, with optionally differentcharacteristics, and two (2) deploying surfaces, plunger surfacesegments F3 and F2 also with optionally different characteristics. Inthe second case, there are still two (2) deploying plunger surfacesegments or surfaces F3 but only one bridging plunger surface segment orsurface F2 and one bridging second material region 2200.

While embodiments of a bladder syringe fluid delivery system and methodsof operation thereof were provided in the foregoing description, thoseskilled in the art may make modifications and alterations to theseembodiments without departing from the scope and spirit of thedisclosure. Accordingly, the foregoing description is intended to beillustrative rather than restrictive. The various embodiments describedhereinabove are defined by the appended claims and all changes that fallwithin the meaning and the range of equivalency of the claims are to beembraced within their scope.

We claim:
 1. A method of manufacturing a syringe comprising the stepsof: providing a cylindrical body of a pressure jacket, providing aplunger element, and molding a cap-bladder assembly comprising forming acap body defining an interior cavity and an outer circumferential edgeportion; and forming a disc-shaped bladder within the interior cavitysuch that an outer circumferential rib of the bladder is molded to wraparound the outer circumferential edge portion of the cap body, whereinforming the disc-shaped bladder comprises forming a membrane portionconfigured to conform to a shape of a distal portion of the plungerelement such that the distal portion of the plunger element and thebladder interact to restrict movement of the bladder outward toward asidewall of the cylindrical body to conserve a membrane materialthickness in a center of the membrane portion as the plunger element isretracted in the cylindrical body.
 2. The method of claim 1, wherein acentral opening is formed in the cap body.
 3. The method of claim 2,wherein the central opening is formed over a convoluted central wellportion formed in the membrane portion of the bladder.
 4. The method ofclaim 2, wherein the central opening is defined by a discharge conduitand a cap element is applied to seal the discharge conduit.
 5. Themethod of claim 4, wherein radial appendages are formed to connect to anannular collar disposed around the discharge conduit.
 6. The method ofclaim 4, wherein the central opening is formed over a convoluted centralwell portion formed in the membrane portion of the bladder.
 7. Themethod of claim 4, wherein the cap element comprises a luer endconnector.
 8. The method of claim 1, wherein forming the membraneportion comprises forming the membrane portion to have extra material ina central area of the membrane portion.
 9. The method of claim 1,wherein forming the membrane portion comprises forming the membraneportion to have a convoluted central well portion.
 10. The method ofclaim 1, wherein forming the membrane portion comprises forming themembrane portion with a non-uniform cross-section.
 11. The method ofclaim 1, wherein forming the membrane portion comprises forming themembrane portion with a plurality of annular ribs.
 12. The method ofclaim 1, wherein forming the membrane portion comprises forming themembrane portion with a plurality of radial ribs.
 13. The method ofclaim 1, wherein the outer circumferential rib of the bladder isconfigured to form a seal with an inner surface of a cap element.